{"id":2004,"date":"2025-12-24T16:39:58","date_gmt":"2025-12-24T08:39:58","guid":{"rendered":"https:\/\/www.sanjiuctf.cn\/?p=2004"},"modified":"2026-01-06T19:11:21","modified_gmt":"2026-01-06T11:11:21","slug":"buuctfcrypto%e7%ac%ac%e4%b8%80%e9%a1%b5wp","status":"publish","type":"post","link":"https:\/\/www.sanjiuctf.cn\/?p=2004","title":{"rendered":"BuuCTFCrypto\u7b2c\u4e00\u9875wp"},"content":{"rendered":"\n<h2 class=\"wp-block-heading\">1.\u4e00\u773c\u5c31\u89e3\u5bc6<\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-421.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"605\" height=\"490\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-421.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2005\"  sizes=\"auto, (max-width: 605px) 100vw, 605px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code>ZmxhZ3tUSEVfRkxBR19PRl9USElTX1NUUklOR30=<\/code><\/pre>\n\n\n\n<p>base64\u89e3\u7801<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-422.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"700\" height=\"41\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-422.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2006\"  sizes=\"auto, (max-width: 700px) 100vw, 700px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{THE_FLAG_OF_THIS_STRING}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">2.MD5<\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-423.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"599\" height=\"174\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-423.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2007\"  sizes=\"auto, (max-width: 599px) 100vw, 599px\" \/><\/div><\/figure>\n\n\n\n<p>MD5\u5728\u7ebf\u89e3\u5bc6\u5c31\u884c<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-424.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"1020\" height=\"364\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-424.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2008\"  sizes=\"auto, (max-width: 1020px) 100vw, 1020px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{admin1}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">3.Url\u7f16\u7801<\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-425.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"660\" height=\"201\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-425.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2009\"  sizes=\"auto, (max-width: 660px) 100vw, 660px\" \/><\/div><\/figure>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-426.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"295\" height=\"70\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-426.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2010\"\/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{and 1=1}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">4.\u770b\u6211\u56de\u65cb\u8e22<\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-427.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"655\" height=\"236\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-427.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2011\"  sizes=\"auto, (max-width: 655px) 100vw, 655px\" \/><\/div><\/figure>\n\n\n\n<p>Rot13\u89e3\u5bc6<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-428.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"715\" height=\"35\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-428.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2012\"  sizes=\"auto, (max-width: 715px) 100vw, 715px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{5cd1004d-86a5-46d8-b720-beb5ba0417e1}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">5.\u6469\u4e1d<\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-429.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"581\" height=\"225\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-429.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2013\"  sizes=\"auto, (max-width: 581px) 100vw, 581px\" \/><\/div><\/figure>\n\n\n\n<p>\u6469\u65af\u89e3\u5bc6<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-430.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"371\" height=\"100\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-430.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2014\"  sizes=\"auto, (max-width: 371px) 100vw, 371px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{ILOVEYOU}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">6.password<\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-431.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"523\" height=\"281\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-431.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2015\"  sizes=\"auto, (max-width: 523px) 100vw, 523px\" \/><\/div><\/figure>\n\n\n\n<p>\u5f31\u5bc6\u7801\u4e00\u5171\u662f\u4e5d\u4f4d\u90a3\u4e48\u5c31\u662f\u540d\u5b57+\u751f\u65e5\u5c31\u884c<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{zs19900315}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">7.\u53d8\u5f02\u51ef\u6492<\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-432.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"595\" height=\"215\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-432.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2016\"  sizes=\"auto, (max-width: 595px) 100vw, 595px\" \/><\/div><\/figure>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-433.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"665\" height=\"170\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-433.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2017\"  sizes=\"auto, (max-width: 665px) 100vw, 665px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{Caesar_variation}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">8.Quoted-Printable<\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-434.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"774\" height=\"261\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-434.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2018\"  sizes=\"auto, (max-width: 774px) 100vw, 774px\" \/><\/div><\/figure>\n\n\n\n<p>Quoted-Printable\u7f16\u7801\u89e3\u7801\u5c31\u884c<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-435.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"500\" height=\"91\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-435.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2019\"  sizes=\"auto, (max-width: 500px) 100vw, 500px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{\u90a3\u4f60\u4e5f\u5f88\u68d2\u54e6}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">9.\u7bf1\u7b06\u5899\u7684\u5f71\u5b50<\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-436.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"615\" height=\"239\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-436.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2020\"  sizes=\"auto, (max-width: 615px) 100vw, 615px\" \/><\/div><\/figure>\n\n\n\n<p>\u53e4\u5178\u5bc6\u7801\u7684\u6805\u680f\u4f4d\u79fb\u5f0f\u5bc6\u7801<\/p>\n\n\n\n<p>\u666e\u901a\u578b13\u680f\u5c31\u51fa\u6765<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-437-1024x526.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"526\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-437-1024x526.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2021\"  sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{wethinkwehavetheflag}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">10.Rabbit<\/h2>\n\n\n\n<p>Rabbit\u89e3\u5bc6\uff0c\u6ca1\u6709\u5bc6\u94a5<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-438.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"676\" height=\"229\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-438.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2022\"  sizes=\"auto, (max-width: 676px) 100vw, 676px\" \/><\/div><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-439-1024x659.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"659\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-439-1024x659.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2023\"  sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{Cute_Rabbit}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">11.RSA<\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-440.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"725\" height=\"264\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-440.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2024\"  sizes=\"auto, (max-width: 725px) 100vw, 725px\" \/><\/div><\/figure>\n\n\n\n<p>RSA \u539f\u7406<\/p>\n\n\n\n<p>RSA \u7b97\u6cd5\u4e2d\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>n=p\u00d7q<em>n<\/em>=<em>p<\/em>\u00d7<em>q<\/em><\/li>\n\n\n\n<li>\u03c6(n)=(p\u22121)\u00d7(q\u22121)<em>\u03c6<\/em>(<em>n<\/em>)=(<em>p<\/em>\u22121)\u00d7(<em>q<\/em>\u22121)<\/li>\n\n\n\n<li>\u516c\u94a5\u5bf9\uff1a(e,n)(<em>e<\/em>,<em>n<\/em>)\uff0c\u5176\u4e2d 1&lt;e&lt;\u03c6(n)1&lt;<em>e<\/em>&lt;<em>\u03c6<\/em>(<em>n<\/em>) \u4e14 gcd\u2061(e,\u03c6(n))=1gcd(<em>e<\/em>,<em>\u03c6<\/em>(<em>n<\/em>))=1<\/li>\n\n\n\n<li>\u79c1\u94a5 d<em>d<\/em> \u6ee1\u8db3\uff1ae\u00d7d\u22611(mod\u03c6(n))<em>e<\/em>\u00d7<em>d<\/em>\u22611(mod<em>\u03c6<\/em>(<em>n<\/em>))<\/li>\n\n\n\n<li>\u5373\uff1ad=e\u22121\u200amod\u200a\u03c6(n)<em>d<\/em>=<em>e<\/em>\u22121mod<em>\u03c6<\/em>(<em>n<\/em>)<\/li>\n<\/ul>\n\n\n\n<p><strong>\u9010\u6b65\u8ba1\u7b97<\/strong><\/p>\n\n\n\n<p>1\uff1a\u8ba1\u7b97 \u03c6(n)<em>\u03c6<\/em>(<em>n<\/em>)<\/p>\n\n\n\n<p>\u03c6(n)=(p\u22121)\u00d7(q\u22121)<em>\u03c6<\/em>(<em>n<\/em>)=(<em>p<\/em>\u22121)\u00d7(<em>q<\/em>\u22121)<\/p>\n\n\n\n<p>\u6b65 2\u4f7f\u7528\u6269\u5c55\u6b27\u51e0\u91cc\u5f97\u7b97\u6cd5\u6c42 d<em>d<\/em><\/p>\n\n\n\n<p>\u89e3\u65b9\u7a0b\uff1ae\u00d7d+k\u00d7\u03c6(n)=1<em>e<\/em>\u00d7<em>d<\/em>+<em>k<\/em>\u00d7<em>\u03c6<\/em>(<em>n<\/em>)=1\uff0c\u6c42 d<em>d<\/em><\/p>\n\n\n\n<p>3\uff1a\u51fa\u7ed3\u679c\u5e76\u683c\u5f0f\u5316<\/p>\n\n\n\n<p>py3\u811a\u672c<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>#!\/usr\/bin\/env python3\n\"\"\"\nRSA \u79c1\u94a5\u53c2\u6570 d \u8ba1\u7b97\u811a\u672c\n\u9898\u76ee\uff1a\np = 473398607161\nq = 4511491\ne = 17\n\u6c42 d\n\"\"\"\n\ndef extended_gcd(a, b):\n    \"\"\"\u6269\u5c55\u6b27\u51e0\u91cc\u5f97\u7b97\u6cd5\n    \u8fd4\u56de (gcd, x, y) \u4f7f\u5f97 ax + by = gcd(a, b)\n    \"\"\"\n    if b == 0:\n        return a, 1, 0\n    else:\n        gcd, x1, y1 = extended_gcd(b, a % b)\n        x = y1\n        y = x1 - (a \/\/ b) * y1\n        return gcd, x, y\n\ndef mod_inverse(e, phi):\n    \"\"\"\u8ba1\u7b97\u6a21\u9006\u5143 d = e^(-1) mod phi\"\"\"\n    gcd, x, y = extended_gcd(e, phi)\n    if gcd != 1:\n        raise ValueError(\"e \u548c phi \u4e0d\u4e92\u8d28\uff0c\u65e0\u6cd5\u8ba1\u7b97\u9006\u5143\")\n    # \u786e\u4fdd d \u4e3a\u6b63\u6570\n    d = x % phi\n    return d\n\ndef main():\n    # \u5df2\u77e5\u53c2\u6570\n    p = 473398607161\n    q = 4511491\n    e = 17\n\n    print(\"&#91;+] \u5df2\u77e5\u53c2\u6570:\")\n    print(f\"    p = {p}\")\n    print(f\"    q = {q}\")\n    print(f\"    e = {e}\")\n    print()\n\n    # \u8ba1\u7b97 n \u548c phi(n)\n    n = p * q\n    phi_n = (p - 1) * (q - 1)\n\n    print(\"&#91;+] \u8ba1\u7b97\u4e2d\u95f4\u503c:\")\n    print(f\"    n = p \u00d7 q = {n}\")\n    print(f\"    \u03c6(n) = (p-1) \u00d7 (q-1) = {phi_n}\")\n    print()\n\n    # \u9a8c\u8bc1 e \u4e0e phi(n) \u662f\u5426\u4e92\u8d28\n    import math\n    gcd = math.gcd(e, phi_n)\n    print(f\"&#91;+] \u9a8c\u8bc1 gcd(e, \u03c6(n)) = gcd({e}, {phi_n}) = {gcd}\")\n    if gcd != 1:\n        print(\"&#91;-] e \u548c \u03c6(n) \u4e0d\u4e92\u8d28\uff0c\u65e0\u6cd5\u8ba1\u7b97\u9006\u5143\uff01\")\n        return\n    print(\"&#91;\u221a] e \u548c \u03c6(n) \u4e92\u8d28\uff0c\u53ef\u4ee5\u8ba1\u7b97\u9006\u5143\")\n    print()\n\n    # \u8ba1\u7b97 d = e^(-1) mod \u03c6(n)\n    d = mod_inverse(e, phi_n)\n\n    print(\"&#91;+] \u8ba1\u7b97\u7ed3\u679c:\")\n    print(f\"    d = e^(-1) mod \u03c6(n) = {d}\")\n    print()\n\n    # \u9a8c\u8bc1\u7ed3\u679c\n    verification = (e * d) % phi_n\n    print(f\"&#91;+] \u9a8c\u8bc1: (e \u00d7 d) mod \u03c6(n) = ({e} \u00d7 {d}) mod {phi_n}\")\n    print(f\"         = {e * d} mod {phi_n}\")\n    print(f\"         = {verification}\")\n    if verification == 1:\n        print(\"&#91;\u221a] \u9a8c\u8bc1\u6210\u529f\uff01\")\n    else:\n        print(\"&#91;-] \u9a8c\u8bc1\u5931\u8d25\uff01\")\n    print()\n\n    # \u8f93\u51fa flag \u683c\u5f0f\n    print(\"&#91;+] Flag \u683c\u5f0f:\")\n    print(f\"    noxCTF{{{d}}}\")\n    print(f\"    \u63d0\u4ea4\u65f6\u66ff\u6362\u4e3a: flag{{{d}}}\")\n\nif __name__ == \"__main__\":\n    main()<\/code><\/pre>\n\n\n\n<figure class=\"wp-block-image size-large\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-441-1024x526.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"526\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-441-1024x526.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2025\"  sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{125631357777427553}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">12.\u4e22\u5931\u7684MD5<\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-442.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"780\" height=\"445\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-442.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2026\"  sizes=\"auto, (max-width: 780px) 100vw, 780px\" \/><\/div><\/figure>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u4ee3\u7801\u66b4\u529b\u679a\u4e3e\u4e09\u4e2a\u672a\u77e5\u5b57\u7b26\uff08ASCII 32-126\uff09\uff0c\u5c06<code>TASC{chr(i)}O3RJMV{chr(j)}WDJKX{chr(k)}ZM<\/code>\u8fdb\u884cMD5\u52a0\u5bc6<\/li>\n\n\n\n<li><strong>\u641c\u7d22\u6761\u4ef6<\/strong>\uff1a\u8981\u6c42MD5\u54c8\u5e0c\u503c\u540c\u65f6\u5305\u542b\uff1a\n<ul class=\"wp-block-list\">\n<li>\u5b50\u4e32 <code>e9032<\/code><\/li>\n\n\n\n<li>\u5b50\u4e32 <code>da<\/code><\/li>\n\n\n\n<li>\u5b50\u4e32 <code>911513<\/code><\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>\u66b4\u529b\u7834\u89e3<\/strong>\uff1a\u4e09\u5c64\u5faa\u73af\u904d\u5386\u6240\u6709\u53ef\u80fd\u7ec4\u5408\uff0895^3 \u2248 857,375\u79cd\uff09<\/li>\n<\/ol>\n\n\n\n<p>py3\u811a\u672c\u5448\u73b0<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>import hashlib\n\nfor i in range(32, 127):\n    for j in range(32, 127):\n        for k in range(32, 127):\n            s = f'TASC{chr(i)}O3RJMV{chr(j)}WDJKX{chr(k)}ZM'\n            md5_hash = hashlib.md5(s.encode()).hexdigest()\n            if 'e9032' in md5_hash and 'da' in md5_hash and '911513' in md5_hash:\n                print(f\"\u5b57\u7b26\u4e32: {s}\")\n                print(f\"MD5: {md5_hash}\")\n                print(f\"flag: flag{{{md5_hash}}}\")\n                exit()<\/code><\/pre>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-443.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"893\" height=\"134\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-443.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2027\"  sizes=\"auto, (max-width: 893px) 100vw, 893px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{e9032994dabac08080091151380478a2}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">13.Alice\u4e0eBob<\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-444.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"608\" height=\"629\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-444.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2028\"  sizes=\"auto, (max-width: 608px) 100vw, 608px\" \/><\/div><\/figure>\n\n\n\n<p>\u5206\u6790<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u7ed9\u5b9a\u6570\u5b57<\/strong>: 98554799767<\/li>\n\n\n\n<li><strong>\u8981\u6c42<\/strong>:\n<ul class=\"wp-block-list\">\n<li>\u5206\u89e3\u4e3a\u4e24\u4e2a\u7d20\u6570\uff08\u8d28\u56e0\u6570\uff09<\/li>\n\n\n\n<li>\u6309\u5c0f\u5230\u5927\u987a\u5e8f\u8fde\u63a5\u6210\u65b0\u6570\u5b57<\/li>\n\n\n\n<li>\u8ba1\u7b97\u65b0\u6570\u5b57\u7684MD5 32\u4f4d\u5c0f\u5199\u54c8\u5e0c\u503c<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>\u8f93\u51fa\u683c\u5f0f<\/strong>: flag{md5_hash}<\/li>\n<\/ol>\n\n\n\n<p><strong>\u89e3\u9898\uff1a<\/strong><\/p>\n\n\n\n<p>\u5206\u89e3\u8d28\u56e0\u6570<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5927\u6574\u6570\uff1a98554799767<\/li>\n\n\n\n<li>\u8bd5\u9664\u6cd5\u627e\u5230\u56e0\u5b50\uff1a101999 \u548c 966233<\/li>\n\n\n\n<li>\u9a8c\u8bc1\uff1a101999 \u00d7 966233 = 98554799767<\/li>\n\n\n\n<li>\u4e24\u4e2a\u56e0\u5b50\u5747\u4e3a\u7d20\u6570<\/li>\n<\/ul>\n\n\n\n<p>\u5408\u6210\u65b0\u6570\u5b57<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u8f83\u5c0f\u7d20\u6570\uff1a101999<\/li>\n\n\n\n<li>\u8f83\u5927\u7d20\u6570\uff1a966233<\/li>\n\n\n\n<li>\u8fde\u63a5\uff1a101999966233<\/li>\n<\/ul>\n\n\n\n<p>\u8ba1\u7b97MD5\u54c8\u5e0c<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u8f93\u5165\uff1a101999966233 \u8f93\u51famd5 \u5c31\u662f\u8fd9\u4e2aflag<\/li>\n<\/ul>\n\n\n\n<p>py3\u811a\u672c\u5448\u73b0\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>import hashlib\nimport math\n\ndef is_prime(n: int) -&gt; bool:\n    \"\"\"\u68c0\u67e5\u4e00\u4e2a\u6570\u662f\u5426\u4e3a\u7d20\u6570\"\"\"\n    if n &lt; 2:\n        return False\n    # \u53ea\u9700\u68c0\u67e5\u5230 sqrt(n)\n    for i in range(2, int(math.isqrt(n)) + 1):\n        if n % i == 0:\n            return False\n    return True\n\ndef factorize(n: int):\n    \"\"\"\u5206\u89e3\u5927\u6574\u6570\u4e3a\u4e24\u4e2a\u7d20\u6570\u56e0\u5b50\"\"\"\n    # \u8bd5\u9664\u6cd5\u67e5\u627e\u56e0\u5b50\n    for i in range(2, int(math.isqrt(n)) + 1):\n        if n % i == 0:  # \u627e\u5230\u56e0\u5b50\n            j = n \/\/ i\n            # \u68c0\u67e5\u4e24\u4e2a\u56e0\u5b50\u662f\u5426\u90fd\u662f\u7d20\u6570\n            if is_prime(i) and is_prime(j):\n                return sorted(&#91;i, j])  # \u8fd4\u56de\u6392\u5e8f\u540e\u7684\u56e0\u5b50\n    return None\n\ndef main():\n    # \u7ed9\u5b9a\u7684\u5927\u6574\u6570\n    n = 98554799767\n\n    # \u5206\u89e3\u8d28\u56e0\u6570\n    factors = factorize(n)\n    if not factors:\n        print(\"\u5206\u89e3\u5931\u8d25\")\n        return\n\n    p, q = factors  # p\u662f\u8f83\u5c0f\u7d20\u6570\uff0cq\u662f\u8f83\u5927\u7d20\u6570\n    print(f\"\u5206\u89e3\u7ed3\u679c: {p} \u00d7 {q} = {n}\")\n\n    # \u5408\u6210\u65b0\u6570\u5b57: \u5c0f\u7684\u653e\u524d\u9762\uff0c\u5927\u7684\u653e\u540e\u9762\n    new_num = int(str(p) + str(q))\n    print(f\"\u5408\u6210\u6570\u5b57: {new_num}\")\n\n    # \u8ba1\u7b97MD5\u54c8\u5e0c\n    md5_hash = hashlib.md5(str(new_num).encode()).hexdigest()\n    print(f\"MD5\u54c8\u5e0c: {md5_hash}\")\n\n    # \u8f93\u51faflag\n    print(f\"flag{{{md5_hash}}}\")\n\nif __name__ == \"__main__\":\n    main()<\/code><\/pre>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-445.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"938\" height=\"273\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-445.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2029\"  sizes=\"auto, (max-width: 938px) 100vw, 938px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{d450209323a847c8d01c6be47c81811a}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">14.\u5927\u5e1d\u7684\u5bc6\u7801\u6b66\u5668<\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-446.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"728\" height=\"300\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-446.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2030\"  sizes=\"auto, (max-width: 728px) 100vw, 728px\" \/><\/div><\/figure>\n\n\n\n<p>\u5bc6\u6587:ComeChina<\/p>\n\n\n\n<p>\u5148\u89e3\u5bc6\u8fd9\u4e2a:FRPHEVGL<\/p>\n\n\n\n<p>\u5f53\u79fb\u4f4d\u91cf=13\uff08ROT13\uff09\uff1a\u89e3\u51fa\u7684\u5355\u8bcd\u6709\u610f\u4e49<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-447.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"310\" height=\"70\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-447.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2031\"  sizes=\"auto, (max-width: 310px) 100vw, 310px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code>SECURITY \u5b89\u5168<\/code><\/pre>\n\n\n\n<p>\u6211\u4eec\u5df2\u7ecf\u77e5\u9053\u504f\u79fb\u91cf\u4e86\u76f4\u63a5\u89e3\u5bc6\u6587<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-448-1024x387.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"387\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-448-1024x387.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2032\"  sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{PbzrPuvan}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">15.rsarsa<\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-449.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"799\" height=\"650\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-449.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2033\"  sizes=\"auto, (max-width: 799px) 100vw, 799px\" \/><\/div><\/figure>\n\n\n\n<p>\u89e3\u5bc6<\/p>\n\n\n\n<p>1\uff1a\u8ba1\u7b97\u6a21\u6570n<\/p>\n\n\n\n<p>n=p\u00d7q<em>n<\/em>=<em>p<\/em>\u00d7<em>q<\/em> \u8ba1\u7b97\u5f972048\u4f4d\u5927\u6574\u6570<\/p>\n\n\n\n<p>2\uff1a\u8ba1\u7b97\u6b27\u62c9\u51fd\u6570\u03c6(n) \u03c6(n)=(p\u22121)\u00d7(q\u22121)<em>\u03c6<\/em>(<em>n<\/em>)=(<em>p<\/em>\u22121)\u00d7(<em>q<\/em>\u22121)<\/p>\n\n\n\n<p>3\uff1a\u8ba1\u7b97\u79c1\u94a5d<\/p>\n\n\n\n<p>\u4f7f\u7528\u6269\u5c55\u6b27\u51e0\u91cc\u5f97\u7b97\u6cd5\uff1ad=e\u22121mod\u2009\u2009\u03c6(n)<em>d<\/em>=<em>e<\/em>\u22121mod<em>\u03c6<\/em>(<em>n<\/em>) \u89e3\u65b9\u7a0b\uff1ae\u00d7d\u22611(mod\u03c6(n))<em>e<\/em>\u00d7<em>d<\/em>\u22611(mod<em>\u03c6<\/em>(<em>n<\/em>))<\/p>\n\n\n\n<p>4\uff1a\u89e3\u5bc6\u6d88\u606f<\/p>\n\n\n\n<p>m=cdmod\u2009\u2009n<em>m<\/em>=*c*<em>d<\/em>mod<em>n<\/em> \u4f7f\u7528\u6a21\u5e42\u8fd0\u7b97\u5feb\u901f\u8ba1\u7b97<\/p>\n\n\n\n<p>py3\u811a\u672c<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code># RSA\u53c2\u6570\np = 9648423029010515676590551740010426534945737639235739800643989352039852507298491399561035009163427050370107570733633350911691280297777160200625281665378483\nq = 11874843837980297032092405848653656852760910154543380907650040190704283358909208578251063047732443992230647903887510065547947313543299303261986053486569407\ne = 65537\nc = 83208298995174604174773590298203639360540024871256126892889661345742403314929861939100492666605647316646576486526217457006376842280869728581726746401583705899941768214138742259689334840735633553053887641847651173776251820293087212885670180367406807406765923638973161375817392737747832762751690104423869019034\n\n# \u8ba1\u7b97n\u548c\u03c6(n)\nn = p * q\nphi_n = (p-1) * (q-1)\n\n# \u6269\u5c55\u6b27\u51e0\u91cc\u5f97\u6c42\u6a21\u9006\u5143d\ndef mod_inverse(a, m):\n    def egcd(a, b):\n        if b == 0:\n            return (1, 0, a)\n        x, y, g = egcd(b, a % b)\n        return (y, x - (a \/\/ b) * y, g)\n\n    x, y, g = egcd(a, m)\n    if g != 1:\n        raise ValueError('\u9006\u5143\u4e0d\u5b58\u5728')\n    return x % m\n\n# \u8ba1\u7b97\u79c1\u94a5d\nd = mod_inverse(e, phi_n)\n\n# RSA\u89e3\u5bc6 m = c^d mod n\nm = pow(c, d, n)\n\nprint(f\"\u89e3\u5bc6\u540e\u7684\u6570\u5b57m: {m}\")\nprint(f\"flag\u683c\u5f0f: flag{{{m}}}\")<\/code><\/pre>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-450.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"930\" height=\"155\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-450.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2034\"  sizes=\"auto, (max-width: 930px) 100vw, 930px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code> flag{5577446633554466577768879988}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">16.Windows\u7cfb\u7edf\u5bc6\u7801<\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-451.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"791\" height=\"495\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-451.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2035\"  sizes=\"auto, (max-width: 791px) 100vw, 791px\" \/><\/div><\/figure>\n\n\n\n<p>\u683c\u5f0f\u5206\u6790<\/p>\n\n\n\n<p>\u8fd9\u662f Windows SAM \u6570\u636e\u5e93\u683c\u5f0f\uff08<code>LM:NTLM<\/code>\uff09\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\u7528\u6237\u540d:RID:LM-Hash:NTLM-Hash:::<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>Administrator:500:...<\/code> &#8211; \u7ba1\u7406\u5458\u8d26\u6237<\/li>\n\n\n\n<li><code>ctf:1002:...<\/code> &#8211; \u7528\u6237\u8d26\u6237<\/li>\n\n\n\n<li>\u683c\u5f0f\uff1a<code>LM:NTLM<\/code>\uff08<code>aad3b435b51404eeaad3b435b51404ee<\/code>\u8868\u793a\u7a7aLM Hash\uff09<\/li>\n<\/ul>\n\n\n\n<p>\u53ea\u6709ctf\u8fd9\u4e2a\u7528\u6237\u6709\u5bc6\u7801\u89e3\u51fa\u5c31\u884c<\/p>\n\n\n\n<p>Guest\u548cAdministrator\u662f\u7a7a\u5bc6\u7801&#8212;&gt;31d6cfe0d16ae931b73c59d7e0c089c0<\/p>\n\n\n\n<p>\u89e3\u51fa\u8fd9\u4e2a\u5c31\u884c<\/p>\n\n\n\n<p>a7fcb22a88038f35a8f39d503e7f0062<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-452.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"890\" height=\"350\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-452.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2036\"  sizes=\"auto, (max-width: 890px) 100vw, 890px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{good-luck}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">17.\u4fe1\u606f\u5316\u65f6\u4ee3\u7684\u6b65\u4f10<\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-453.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"610\" height=\"395\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-453.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2037\"  sizes=\"auto, (max-width: 610px) 100vw, 610px\" \/><\/div><\/figure>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-454.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"591\" height=\"220\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-454.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2038\"  sizes=\"auto, (max-width: 591px) 100vw, 591px\" \/><\/div><\/figure>\n\n\n\n<p>\u4e2d\u6587\u7535\u62a5\u89e3\u7801<\/p>\n\n\n\n<p><a href=\"https:\/\/dianma.bmcx.com\/\">\u4e2d\u6587\u7535\u7801\u67e5\u8be2 &#8211; \u4e2d\u6587\u7535\u7801\u8f6c\u6362 &#8211; \u4e2d\u6587\u7535\u7801\u5bf9\u7167\u8868<\/a><\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-455-1024x444.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"444\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-455-1024x444.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2039\"  sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/div><\/figure>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-456.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"509\" height=\"59\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-456.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2040\"  sizes=\"auto, (max-width: 509px) 100vw, 509px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{\u8ba1\u7b97\u673a\u8981\u4ece\u5a03\u5a03\u6293\u8d77}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">18.\u51ef\u6492\uff1f\u66ff\u6362\uff1f\u5475\u5475!<\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-457.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"930\" height=\"431\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-457.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2041\"  sizes=\"auto, (max-width: 930px) 100vw, 930px\" \/><\/div><\/figure>\n\n\n\n<p>\u51ef\u6492\u5bc6\u7801\u66ff\u6362\uff0cMTHJ=flag<\/p>\n\n\n\n<p><a href=\"https:\/\/quipqiup.com\/\">quipqiup &#8211; cryptoquip and cryptogram solver<\/a><\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-458-1024x605.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"605\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-458-1024x605.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2042\"  sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{substitutioncipherdecryptionisalwayseasyjustlikeapieceofcake}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">19.\u840c\u840c\u54d2\u7684\u516b\u6212<\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-459.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"810\" height=\"526\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-459.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2043\"  sizes=\"auto, (max-width: 810px) 100vw, 810px\" \/><\/div><\/figure>\n\n\n\n<p>\u732a\u5708\u66ff\u6362\u5f0f\u5bc6\u7801<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-460.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"645\" height=\"789\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-460.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2044\"  sizes=\"auto, (max-width: 645px) 100vw, 645px\" \/><\/div><\/figure>\n\n\n\n<p>\u5bf9\u7167\u5c31\u884c \u5c0f\u5199<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{whenthepigwanttoeat}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">20.\u6743\u9650\u83b7\u5f97\u7b2c\u4e00\u6b65<\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-461.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"609\" height=\"428\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-461.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2045\"  sizes=\"auto, (max-width: 609px) 100vw, 609px\" \/><\/div><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-462-1024x145.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"145\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-462-1024x145.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2046\"  sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/div><\/figure>\n\n\n\n<p>\u89e3\u51fawindows\u5bc6\u7801<\/p>\n\n\n\n<p>\u7ed3\u6784\u5206\u6790\u5982\u4e0b\uff1a<br><code>Administrator:500:806EDC27AA52E314AAD3B435B51404EE:F4AD50F57683D4260DFD48AA351A17A8:::<\/code><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u7528\u6237<\/strong>: Administrator<\/li>\n\n\n\n<li><strong>RID<\/strong>: 500<\/li>\n\n\n\n<li><strong>LM Hash<\/strong>: <code>806EDC27AA52E314AAD3B435B51404EE<\/code><\/li>\n\n\n\n<li><strong>NT Hash<\/strong> (\u901a\u5e38\u5b58\u653e NTLM \u54c8\u5e0c\u7684\u4f4d\u7f6e): <code>F4AD50F57683D4260DFD48AA351A17A8<\/code><\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>F4AD50F57683D4260DFD48AA351A17A8<\/code><\/pre>\n\n\n\n<p>\u89e3\u5bc6\u8fd9\u4e2a\u5c31\u884c<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-463-1024x432.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"432\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-463-1024x432.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2047\"  sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{3617656}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">21.RSA1<\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-464.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"790\" height=\"605\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-464.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2048\"  sizes=\"auto, (max-width: 790px) 100vw, 790px\" \/><\/div><\/figure>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u5df2\u77e5 RSA-CRT \u53c2\u6570\uff1a<code>p, q, dp, dq, c<\/code>\u3002<\/li>\n\n\n\n<li>\u8ba1\u7b97 <code>m1 = c^dp mod p<\/code> \u548c <code>m2 = c^dq mod q<\/code>\u3002<\/li>\n\n\n\n<li>\u8ba1\u7b97 <code>q_inv = q^{-1} mod p<\/code>\u3002<\/li>\n\n\n\n<li>\u5229\u7528\u4e2d\u56fd\u5269\u4f59\u5b9a\u7406\uff08CRT\uff09\u516c\u5f0f\uff1a<code>m = m2 + ((m1 - m2) * q_inv mod p) * q<\/code>\u3002<\/li>\n\n\n\n<li>\u5c06\u5f97\u5230\u7684\u6574\u6570 <code>m<\/code> \u8f6c\u6362\u4e3a\u5b57\u8282\u4e32\uff0c\u5373\u4e3a flag\u3002<\/li>\n<\/ol>\n\n\n\n<p>py3\u811a\u672c<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>import binascii\n\np = 8637633767257008567099653486541091171320491509433615447539162437911244175885667806398411790524083553445158113502227745206205327690939504032994699902053229\nq = 12640674973996472769176047937170883420927050821480010581593137135372473880595613737337630629752577346147039284030082593490776630572584959954205336880228469\ndp = 6500795702216834621109042351193261530650043841056252930930949663358625016881832840728066026150264693076109354874099841380454881716097778307268116910582929\ndq = 783472263673553449019532580386470672380574033551303889137911760438881683674556098098256795673512201963002175438762767516968043599582527539160811120550041\nc = 24722305403887382073567316467649080662631552905960229399079107995602154418176056335800638887527614164073530437657085079676157350205351945222989351316076486573599576041978339872265925062764318536089007310270278526159678937431903862892400747915525118983959970607934142974736675784325993445942031372107342103852\n\n# \u8ba1\u7b97 n\nn = p * q\n\n# \u8ba1\u7b97 m1 \u548c m2\nm1 = pow(c, dp, p)\nm2 = pow(c, dq, q)\n\n# \u8ba1\u7b97 q \u5173\u4e8e p \u7684\u6a21\u9006\nq_inv = pow(q, -1, p)\n\n# \u4f7f\u7528 CRT \u8ba1\u7b97\u660e\u6587 m\nh = (q_inv * (m1 - m2)) % p\nm = m2 + h * q\n\n# \u5c06\u6574\u6570\u8f6c\u6362\u4e3a\u5b57\u8282\u4e32\uff08flag\uff09\nflag_bytes = m.to_bytes((m.bit_length() + 7) \/\/ 8, 'big')\nprint(flag_bytes.decode())<\/code><\/pre>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-465.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"739\" height=\"100\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-465.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2049\"  sizes=\"auto, (max-width: 739px) 100vw, 739px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{W31c0m3_70_Ch1n470wn}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">22.\u4f20\u7edf\u77e5\u8bc6+\u53e4\u5178\u5bc6\u7801<\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-466.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"600\" height=\"311\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-466.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2050\"  sizes=\"auto, (max-width: 600px) 100vw, 600px\" \/><\/div><\/figure>\n\n\n\n<p>\u6839\u636e\u5e72\u652f\u5e8f\u5217\u548c\u201c+\u7532\u5b50\u201d\u7684\u63d0\u793a\uff0c\u5c06\u6bcf\u4e2a\u5e72\u652f\u8f6c\u6362\u4e3a\u516d\u5341\u7532\u5b50\u4e2d\u7684\u5e8f\u53f7\uff08\u4ece1\u5f00\u59cb\uff09\uff0c\u5f97\u5230\u5e8f\u5217 <code>[28, 30, 23, 8, 17, 10, 16, 30]<\/code>\u3002\u7531\u4e8e\u201c\u7532\u5b50\u201d\u4ee3\u8868\u4e00\u4e2a60\u5e74\u7684\u5468\u671f\uff0c\u5c06\u6bcf\u4e2a\u5e8f\u53f7\u52a0\u4e0a60\uff0c\u5f97\u5230 <code>[88, 90, 83, 68, 77, 70, 76, 90]<\/code>\uff0c\u5bf9\u5e94ASCII\u5b57\u7b26 <code>X, Z, S, D, M, F, L, Z<\/code>\uff0c\u7ec4\u5408\u540e\u5f97\u5230\u5b57\u7b26\u4e32 <code>XZSDMFLZ<\/code><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>gan = &#91;'\u7532','\u4e59','\u4e19','\u4e01','\u620a','\u5df1','\u5e9a','\u8f9b','\u58ec','\u7678']\nzhi = &#91;'\u5b50','\u4e11','\u5bc5','\u536f','\u8fb0','\u5df3','\u5348','\u672a','\u7533','\u9149','\u620c','\u4ea5']\njiazi = &#91;gan&#91;i%10]+zhi&#91;i%12] for i in range(60)]\ngiven = &#91;'\u8f9b\u536f','\u7678\u5df3','\u4e19\u620c','\u8f9b\u672a','\u5e9a\u8fb0','\u7678\u9149','\u5df1\u536f','\u7678\u5df3']\nindices = &#91;jiazi.index(g)+1 for g in given]\nflag = ''.join(chr(i+60) for i in indices)\nprint(f'CTF{{{flag}}}')<\/code><\/pre>\n\n\n\n<p>XZSDMFLZ \u5728\u8fdb\u884c\u89e3\u5bc6<\/p>\n\n\n\n<p><strong>\u6805\u680f\u5bc6\u7801\u89e3\u5bc6<\/strong><\/p>\n\n\n\n<p>\u680f\u6570\u4e3a 2<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-467.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"365\" height=\"110\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-467.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2051\"  sizes=\"auto, (max-width: 365px) 100vw, 365px\" \/><\/div><\/figure>\n\n\n\n<p>XMZFSLDZ<\/p>\n\n\n\n<p><strong>\u51ef\u6492\u89e3\u5bc6<\/strong><\/p>\n\n\n\n<p>\u5f53\u4f4d\u79fb\u91cf\u4e3a 5 \u89e3\u51fa\u6709\u610f\u4e49\u7684\u5b57\u7b26\u4e32<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-468.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"559\" height=\"195\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-468.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2052\"  sizes=\"auto, (max-width: 559px) 100vw, 559px\" \/><\/div><\/figure>\n\n\n\n<p>Key\u503c\u4e3a\uff1a<\/p>\n\n\n\n<p><strong>CTF{SHUANGYU}<\/strong><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{SHUANGYU}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">23.\u4e16\u4e0a\u65e0\u96be\u4e8b<\/h2>\n\n\n\n<pre class=\"wp-block-code\"><code>VIZZB IFIUOJBWO NVXAP OBC XZZ UKHVN IFIUOJBWO HB XVIXW XAW VXFI X QIXN VBD KQ IFIUOJBWO WBKAH NBWXO VBD XJBCN NKG QLKEIU DI XUI VIUI DKNV QNCWIANQ XN DXPIMKIZW VKHV QEVBBZ KA XUZKAHNBA FKUHKAKX XAW DI VXFI HBN QNCWIANQ NCAKAH KA MUBG XZZ XEUBQQ XGIUKEX MUBG PKAWIUHXUNIA NVUBCHV 12NV HUXWI XAW DI XUI SCQN QB HZXW NVXN XZZ EBCZW SBKA CQ NBWXO XAW DI DXAN NB NVXAP DXPIMKIZW MBU JIKAH QCEV XA BCNQNXAWKAH VBQN HKFI OBCUQIZFIQ X JKH UBCAW BM XLLZXCQI XAW NVI PIO KQ 640I11012805M211J0XJ24MM02X1IW09<\/code><\/pre>\n\n\n\n<p><strong>\u5bc6\u6587\u5206\u6790<\/strong><br>\u89c2\u5bdf\u5bc6\u6587 <code>VIZZB IFIUOJBWO...<\/code>\uff0c\u5b83\u7684\u8bcd\u957f\u5206\u5e03\u548c\u6807\u70b9\u7b26\u53f7\u975e\u5e38\u7b26\u5408\u82f1\u8bed\u53e5\u5b50\u7684\u7279\u5f81\u3002\u7531\u4e8e\u63d0\u793a\u63d0\u5230\u201c\u6beb\u65e0\u89c4\u5f8b\u201d\uff0c\u901a\u5e38\u6307\u7684\u662f<strong>\u5355\u8868\u66ff\u6362\u5bc6\u7801<\/strong>\uff08Monoalphabetic Substitution Cipher\uff09\uff0c\u5373\u5b57\u6bcd\u8868\u4e2d\u7684\u6bcf\u4e2a\u5b57\u6bcd\u90fd\u88ab\u66ff\u6362\u6210\u4e86\u53e6\u4e00\u4e2a\u56fa\u5b9a\u7684\u5b57\u6bcd\u3002<\/p>\n\n\n\n<p>\u5bc6\u6587\u5f00\u5934\u7684 <code>VIZZB IFIUOJBWO<\/code> \u770b\u8d77\u6765\u50cf\u662f\u4e00\u4e2a\u95ee\u5019\u8bed\u3002<\/p>\n\n\n\n<p>\u5c1d\u8bd5\u731c\u6d4b\uff1a<br><code>VIZZB<\/code> = <code>HELLO<\/code><br><code>IFIUOJBWO<\/code> = <code>EVERYBODY<\/code><\/p>\n\n\n\n<p>\u6839\u636e\u9898\u76ee\u63cf\u8ff0\u201c\u67d0\u56fd\u73b0\u4efb\u603b\u7edf\u5916\u53d1\u7684\u4e00\u6bb5\u6307\u4ee4\u201d\uff0c\u641c\u7d22 <code>HELLO EVERYBODY<\/code> \u5f00\u5934\u7684\u603b\u7edf\u6f14\u8bb2\uff0c\u53ef\u4ee5\u53d1\u73b0\u8fd9\u662f <strong>\u7f8e\u56fd\u524d\u603b\u7edf\u5965\u5df4\u9a6c\uff08Barack Obama\uff09<\/strong> \u5728 2009 \u5e74\u5f17\u5409\u5c3c\u4e9a\u5dde\u97e6\u514b\u83f2\u5c14\u5fb7\u9ad8\u4e2d\uff08Wakefield High School\uff09\u505a\u7684\u5f00\u5b66\u6f14\u8bb2\u3002<\/p>\n\n\n\n<p>\u5bf9\u7167\u539f\u6587\u548c\u5bc6\u6587\uff0c\u6211\u4eec\u53ef\u4ee5\u63a8\u5bfc\u51fa\u5b8c\u6574\u7684\u66ff\u6362\u8868\u3002<br>\u539f\u6587\u7247\u6bb5\uff1a<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p>&#8220;Hello everybody. Thank you. Thank you all. Right. Everybody go ahead and have a seat. How is everybody doing today? &#8230; and the key is &#8230;&#8221;<\/p>\n<\/blockquote>\n\n\n\n<p>\u5bc6\u6587\u5bf9\u5e94\u90e8\u5206\uff1a<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<pre class=\"wp-block-code\"><code>VIZZB IFIUOJBWO NVXAP OBC XZZ UKHVN ... XAW NVI PIO KQ ...<\/code><\/pre>\n<\/blockquote>\n\n\n\n<pre class=\"wp-block-code\"><code>\u5bc6\u6587  \u660e\u6587  \u52a9\u8bb0\u5355\u8bcd (\u5bc6\u6587$to$\u660e\u6587)\nA   N   XAW $to$ AND\nB   O   VIZZB $to$ HELLO\nC   U   OBC $to$ YOU\nD   W   VBD $to$ HOW\nE   C   XEUBQQ $to$ ACROSS\nF   V   IFIUOJBWO $to$ EVERYBODY\nG   M   MUBG $to$ FROM\nH   G   HB $to$ GO\nI   E   \u2605 \u7528\u4e8eFlag (VIZZB $to$ HELLO)\nJ   B   \u2605 \u7528\u4e8eFlag (IFIUOJBWO $to$ EVERYBODY)\nK   I   KQ $to$ IS\nL   P   QLKEIU $to$ SPIDER\nM   F   \u2605 \u7528\u4e8eFlag (MUBG $to$ FROM)\nN   T   NVXAP $to$ THANK\nO   Y   OBC $to$ YOU\nP   K   NVXAP $to$ THANK\nQ   S   QIXN $to$ SEAT\nS   J   SCQN $to$ JUST\nU   R   IFIUOJBWO $to$ EVERYBODY\nV   H   VIZZB $to$ HELLO\nW   D   \u2605 \u7528\u4e8eFlag (XABW $to$ AND)\nX   A   \u2605 \u7528\u4e8eFlag (XZZ $to$ ALL)\nZ   L   VIZZB $to$ HELLO<\/code><\/pre>\n\n\n\n<p>\u6211\u4eec\u53ef\u4ee5\u786e\u8ba4\u6620\u5c04\u5173\u7cfb\u662f\u6b63\u786e\u7684\uff0c\u7279\u522b\u662f\u6700\u540e\u4e00\u53e5\uff1a<br>\u5bc6\u6587\uff1a<code>XAW NVI PIO KQ<\/code><br>\u660e\u6587\uff1a<code>AND THE KEY IS<\/code><\/p>\n\n\n\n<p><strong>\u89e3\u5bc6 Key \u503c<\/strong><br>\u5bc6\u6587\u7684\u6700\u540e\u7ed9\u51fa\u4e86 Key \u7684\u52a0\u5bc6\u5b57\u7b26\u4e32\uff1a<br><code>640I11012805M211J0XJ24MM02X1IW09<\/code><\/p>\n\n\n\n<p>\u6839\u636e\u9898\u76ee\u8981\u6c42\uff0832\u4f4d\uff0c\u5305\u542b\u5c0f\u5199\u5b57\u6bcd\uff09\uff0c\u6211\u4eec\u9700\u8981\u7528\u540c\u6837\u7684\u66ff\u6362\u8868\u5c06\u8fd9\u4e2a\u5b57\u7b26\u4e32\u4e2d\u7684\u5927\u5199\u5b57\u6bcd\u89e3\u5bc6\u8fd8\u539f\u4e3a\u5c0f\u5199\u5b57\u6bcd\u3002<\/p>\n\n\n\n<p><strong>\u66ff\u6362\u8fc7\u7a0b\uff1a<\/strong><br><code>640<\/code><strong><code>I<\/code><\/strong><code>11012805<\/code><strong><code>M<\/code><\/strong><code>211<\/code><strong><code>J<\/code><\/strong><code>0<\/code><strong><code>X<\/code><\/strong> <strong><code>J<\/code><\/strong><code>24<\/code><strong><code>M<\/code><\/strong> <strong><code>M<\/code><\/strong><code>02<\/code><strong><code>X<\/code><\/strong><code>1<\/code><strong><code>I<\/code><\/strong> <strong><code>W<\/code><\/strong><code>09<\/code><br><code>640<\/code><strong><code>e<\/code><\/strong><code>11012805<\/code><strong><code>f<\/code><\/strong><code>211<\/code><strong><code>b<\/code><\/strong><code>0<\/code><strong><code>a<\/code><\/strong> <strong><code>b<\/code><\/strong><code>24<\/code><strong><code>f<\/code><\/strong> <strong><code>f<\/code><\/strong><code>02<\/code><strong><code>a<\/code><\/strong><code>1<\/code><strong><code>e<\/code><\/strong> <strong><code>d<\/code><\/strong><code>09<\/code><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{640e11012805f211b0ab24ff02a1ed09}<\/code><\/pre>\n\n\n\n<p>\u5148\u8f6c\u6362\u6210\u5c0f\u5199<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>vizzb ifiuojbwo nvxap obc xzz ukhvn ifiuojbwo hb xvixw xaw vxfi x qixn vbd kq ifiuojbwo wbkah nbwxo vbd xjbcn nkg qlkeiu di xui viui dknv qncwianq xn dxpimkizw vkhv qevbbz ka xuzkahnba fkuhkakx xaw di vxfi hbn qncwianq ncakah ka mubg xzz ebczw sbka cq nbwxo xaw di dxan nb nvxap dxpimkizw mbu jikah qcev xa bcqnqxawkah vbqn hkfi obcuqizfiq x jkh ubciaw bm xllzxcqi xaw nvi pio kq 640i11012805m211j0xj24mm02x1iw09<\/code><\/pre>\n\n\n\n<p>\u53ef\u4ee5\u7528https:\/\/quipqiup.com\/ \u66b4\u529b\u7834\u89e3<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-469-1024x537.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"537\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-469-1024x537.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2053\"  sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/div><\/figure>\n\n\n\n<p>\u76f4\u63a5\u51fa\u6765\u4e86<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{640e11012805f211b0ab24ff02a1ed09}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">24.Unencode<\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-470.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"665\" height=\"255\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-470.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2054\"  sizes=\"auto, (max-width: 665px) 100vw, 665px\" \/><\/div><\/figure>\n\n\n\n<p>UUencode\u89e3\u7801<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-471.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"649\" height=\"40\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-471.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2055\"  sizes=\"auto, (max-width: 649px) 100vw, 649px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{dsdasdsa99877LLLKK}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">25.[AFCTF2018]Morse<\/h2>\n\n\n\n<pre class=\"wp-block-code\"><code>-....\/.----\/-....\/-....\/-....\/...--\/--...\/....-\/-....\/-....\/--...\/-...\/...--\/.----\/--...\/...--\/..---\/--...\/--...\/....-\/.....\/..-.\/--...\/...--\/...--\/-----\/.....\/..-.\/...--\/...--\/...--\/....-\/...--\/.....\/--...\/----.\/--...\/-..<\/code><\/pre>\n\n\n\n<p>\u6469\u65af\u89e3\u7801<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-472.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"671\" height=\"76\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-472.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2056\"  sizes=\"auto, (max-width: 671px) 100vw, 671px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code>61666374667B317327745F73305F333435797D<\/code><\/pre>\n\n\n\n<p>\u5341\u516d\u8fdb\u5236\u8f6cASCII<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-473.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"581\" height=\"125\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-473.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2057\"  sizes=\"auto, (max-width: 581px) 100vw, 581px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{1s't_s0_345y}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">26.old-fashion<\/h2>\n\n\n\n<p>\u53c8\u662f\u4e00\u4e2a\u5355\u8868\u66ff\u6362\u7684\u5bc6\u7801\u9898\u76ee<\/p>\n\n\n\n<p>\u5355\u8868\u66ff\u6362\u5bc6\u7801\uff08Monoalphabetic Substitution Cipher\uff09<strong>\u9898\u76ee\uff0c\u4f46\u5305\u542b\u4e86\u4e00\u4e2a\u9677\u9631\uff1a<\/strong>\u5bc6\u6587\u5728\u7b2c\u4e00\u53e5\u5206\u53f7\u4e4b\u540e\u66f4\u6362\u4e86\u66ff\u6362\u8868\uff08\u5bc6\u94a5\uff09**\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-474.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"796\" height=\"364\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-474.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2058\"  sizes=\"auto, (max-width: 796px) 100vw, 796px\" \/><\/div><\/figure>\n\n\n\n<p><a href=\"https:\/\/quipqiup.com\/\">quipqiup &#8211; cryptoquip and cryptogram solver<\/a> \u76f4\u63a5\u51fa<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-475-1024x558.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"558\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-475-1024x558.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2059\"  sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{n1_2hen-d3_hu1-mi-ma_a}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">27.RSA3<\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-476.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"794\" height=\"835\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-476.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2060\"  sizes=\"auto, (max-width: 794px) 100vw, 794px\" \/><\/div><\/figure>\n\n\n\n<p>\u5178\u578b\u7684RSA\u5171\u6a21\u653b\u51fb\uff08Common Modulus Attack\uff09\u573a\u666f\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u4e24\u4e2a\u5bc6\u6587c1\u548cc2\u4f7f\u7528\u76f8\u540c\u7684\u6a21\u6570n\uff0c\u4f46\u4e0d\u540c\u7684\u516c\u94a5\u6307\u6570e1\u548ce2\u52a0\u5bc6<\/li>\n\n\n\n<li>e1\u548ce2\u4e92\u8d28\uff08gcd(e1, e2) = 1\uff09<\/li>\n\n\n\n<li>\u7531\u4e8es\u00b7e1 + t\u00b7e2 = 1\uff0c\u6211\u4eec\u53ef\u4ee5\u8ba1\u7b97 m = (c1^s \u00b7 c2^t) mod n \u6062\u590d\u539f\u59cb\u660e\u6587<\/li>\n<\/ul>\n\n\n\n<p><strong>RSA\u52a0\u5bc6\u539f\u7406<\/strong><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\u9009\u62e9\u4e24\u4e2a\u5927\u8d28\u6570p, q\uff0c\u8ba1\u7b97n = p\u00b7q\n\u9009\u62e9\u516c\u94a5\u6307\u6570e\uff0c\u4f7fgcd(e, \u03c6(n)) = 1\uff0c\u5176\u4e2d\u03c6(n) = (p-1)(q-1)\n\u5bc6\u6587c = m^e mod n\uff0c\u5176\u4e2dm\u662f\u539f\u59cb\u660e\u6587<\/code><\/pre>\n\n\n\n<p><strong>\u5171\u6a21\u653b\u51fb\u539f\u7406<\/strong><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\u5f53\u540c\u4e00\u660e\u6587m\u7528\u76f8\u540c\u6a21\u6570n\uff0c\u4f46\u4e0d\u540c\u6307\u6570e1\u548ce2\u52a0\u5bc6\uff1a\n- c1 = m^e1 mod n\n- c2 = m^e2 mod n\n\u82e5gcd(e1, e2) = 1\uff0c\u53ef\u7528\u6269\u5c55\u6b27\u51e0\u91cc\u5f97\u7b97\u6cd5\u627e\u5230s\u548ct\uff0c\u4f7f\u5f97s\u00b7e1 + t\u00b7e2 = 1\n\u901a\u8fc7\u8ba1\u7b97 m = (c1^s \u00b7 c2^t) mod n \u6062\u590d\u539f\u59cb\u660e\u6587\uff1a\nm = m^(s\u00b7e1+t\u00b7e2) = (m^e1)^s \u00b7 (m^e2)^t = c1^s \u00b7 c2^t (mod n)<\/code><\/pre>\n\n\n\n<p><strong>\u8d1f\u6307\u6570\u5904\u7406<\/strong><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\u5f53s\u6216t\u4e3a\u8d1f\u65f6\uff0c\u65e0\u6cd5\u76f4\u63a5\u8ba1\u7b97c^s mod n\n\u9700\u5148\u8ba1\u7b97\u6a21\u9006\u5143\uff1a\u82e5s &lt; 0\uff0c\u8ba1\u7b97c1_inv = c1^(-1) mod n\n\u7136\u540e\u8ba1\u7b97c1_inv^(-s) mod n \u66ff\u4ee3 c1^s mod n\n<\/code><\/pre>\n\n\n\n<p>py3\u89e3\u5bc6\u811a\u672c<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>import math\nfrom Crypto.Util.number import long_to_bytes\n\n# \u53c2\u6570\nn = 22708078815885011462462049064339185898712439277226831073457888403129378547350292420267016551819052430779004755846649044001024141485283286483130702616057274698473611149508798869706347501931583117632710700787228016480127677393649929530416598686027354216422565934459015161927613607902831542857977859612596282353679327773303727004407262197231586324599181983572622404590354084541788062262164510140605868122410388090174420147752408554129789760902300898046273909007852818474030770699647647363015102118956737673941354217692696044969695308506436573142565573487583507037356944848039864382339216266670673567488871508925311154801\nc1 = 22322035275663237041646893770451933509324701913484303338076210603542612758956262869640822486470121149424485571361007421293675516338822195280313794991136048140918842471219840263536338886250492682739436410013436651161720725855484866690084788721349555662019879081501113222996123305533009325964377798892703161521852805956811219563883312896330156298621674684353919547558127920925706842808914762199011054955816534977675267395009575347820387073483928425066536361482774892370969520740304287456555508933372782327506569010772537497541764311429052216291198932092617792645253901478910801592878203564861118912045464959832566051361\nc2 = 18702010045187015556548691642394982835669262147230212731309938675226458555210425972429418449273410535387985931036711854265623905066805665751803269106880746769003478900791099590239513925449748814075904017471585572848473556490565450062664706449128415834787961947266259789785962922238701134079720414228414066193071495304612341052987455615930023536823801499269773357186087452747500840640419365011554421183037505653461286732740983702740822671148045619497667184586123657285604061875653909567822328914065337797733444640351518775487649819978262363617265797982843179630888729407238496650987720428708217115257989007867331698397\ne1 = 11187289\ne2 = 9647291\n\n# \u9a8c\u8bc1e1\u548ce2\u4e92\u8d28\nif math.gcd(e1, e2) != 1:\n    exit()\n\n# \u6269\u5c55\u6b27\u51e0\u91cc\u5f97\u7b97\u6cd5\ndef egcd(a, b):\n    if a == 0:\n        return (b, 0, 1)\n    g, y, x = egcd(b % a, a)\n    return (g, x - (b \/\/ a) * y, y)\n\ng, s, t = egcd(e1, e2)\n\n# \u8ba1\u7b97\u660e\u6587\npart1 = pow(c1, s, n) if s &gt;= 0 else pow(pow(c1, -1, n), -s, n)\npart2 = pow(c2, t, n) if t &gt;= 0 else pow(pow(c2, -1, n), -t, n)\nm = (part1 * part2) % n\n\nprint(f\"Flag: {long_to_bytes(m).decode()}\")<\/code><\/pre>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-477.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"794\" height=\"70\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-477.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2061\"  sizes=\"auto, (max-width: 794px) 100vw, 794px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{49d91077a1abcb14f1a9d546c80be9ef}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">28.RSA2<\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-478.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"790\" height=\"575\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-478.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2062\"  sizes=\"auto, (max-width: 790px) 100vw, 790px\" \/><\/div><\/figure>\n\n\n\n<p><strong>\u5df2\u77e5dp\u653b\u51fb<\/strong><\/p>\n\n\n\n<p><strong>\u4e3a\u4ec0\u4e48dp\u4f1a\u6cc4\u9732\u5bfc\u81f4RSA\u88ab\u7834\u89e3\uff1f<\/strong><\/p>\n\n\n\n<p>\u5728RSA\u4e2d\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>dp = d mod (p-1)<\/code><\/li>\n\n\n\n<li>\u7531RSA\u6027\u8d28\uff1a<code>e\u00b7d \u2261 1 mod \u03c6(n)<\/code>\uff0c\u5176\u4e2d<code>\u03c6(n) = (p-1)(q-1)<\/code><\/li>\n\n\n\n<li>\u56e0\u6b64\uff1a<code>e\u00b7dp \u2261 1 mod (p-1)<\/code>\uff0c\u5373<code>e\u00b7dp - 1 = k\u00b7(p-1)<\/code><\/li>\n<\/ul>\n\n\n\n<p><strong>\u653b\u51fb\u6b65\u9aa4\uff1a<\/strong><\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u8ba1\u7b97 <code>temp = e\u00b7dp - 1<\/code>\uff08\u5b83\u662fp-1\u7684\u500d\u6570\uff09<\/li>\n\n\n\n<li>\u968f\u673a\u9009\u62e9\u6574\u6570g\uff0c\u8ba1\u7b97 <code>x = g^temp mod n<\/code><\/li>\n\n\n\n<li>\u7531\u4e8etemp\u662fp-1\u7684\u500d\u6570\uff0c\u6839\u636e\u8d39\u9a6c\u5c0f\u5b9a\u7406\uff1a<code>x \u2261 1 mod p<\/code><\/li>\n\n\n\n<li>\u8ba1\u7b97 <code>p = gcd(x-1, n)<\/code> \u5f97\u5230p<\/li>\n\n\n\n<li>\u901a\u8fc7 <code>q = n\/p<\/code> \u8ba1\u7b97q<\/li>\n\n\n\n<li>\u6062\u590d\u79c1\u94a5d\u5e76\u89e3\u5bc6\uff1a<code>m = c^d mod n<\/code><\/li>\n<\/ol>\n\n\n\n<p>py3\u89e3\u9898\u811a\u672c<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>import math\nimport random\nfrom Crypto.Util.number import long_to_bytes\n\n# \u9898\u76ee\u7ed9\u5b9a\u53c2\u6570\ne = 65537\nn = 248254007851526241177721526698901802985832766176221609612258877371620580060433101538328030305219918697643619814200930679612109885533801335348445023751670478437073055544724280684733298051599167660303645183146161497485358633681492129668802402065797789905550489547645118787266601929429724133167768465309665906113\ndp = 905074498052346904643025132879518330691925174573054004621877253318682675055421970943552016695528560364834446303196939207056642927148093290374440210503657\nc = 140423670976252696807533673586209400575664282100684119784203527124521188996403826597436883766041879067494280957410201958935737360380801845453829293997433414188838725751796261702622028587211560353362847191060306578510511380965162133472698713063592621028959167072781482562673683090590521214218071160287665180751\n\n# 1. \u5229\u7528dp\u6062\u590dp\ntemp = e * dp - 1\nfor i in range(10):  # \u901a\u5e38\u51e0\u6b21\u5c1d\u8bd5\u5c31\u80fd\u6210\u529f\n    g = random.randint(2, n-1)\n    x = pow(g, temp, n)\n    p = math.gcd(x - 1, n)\n    if 1 &lt; p &lt; n:  # \u627e\u5230\u6b63\u786e\u7684p\n        q = n \/\/ p\n        break\n\n# 2. \u8ba1\u7b97\u79c1\u94a5d\u5e76\u89e3\u5bc6\nphi = (p - 1) * (q - 1)\nd = pow(e, -1, phi)\nm = pow(c, d, n)\n\n# 3. \u8f6c\u6362\u4e3aflag\nflag = long_to_bytes(m).decode()\nprint(f\"Flag: {flag}\")<\/code><\/pre>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-479.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"820\" height=\"141\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-479.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2063\"  sizes=\"auto, (max-width: 820px) 100vw, 820px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{wow_leaking_dp_breaks_rsa?_98924743502}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">29.\u8fd8\u539f\u5927\u5e08<\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-480.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"596\" height=\"505\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-480.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2064\"  sizes=\"auto, (max-width: 596px) 100vw, 596px\" \/><\/div><\/figure>\n\n\n\n<p><strong>\u9898\u76ee\u5206\u6790<\/strong><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\u795e\u79d8\u5b57\u7b26\u4e32\uff1a`TASC?O3RJMV?WDJKX?ZM`\uff083\u4e2a\u95ee\u53f7\u662f\u672a\u77e5\u5927\u5199\u5b57\u6bcd\uff09\n\u5df2\u77e5\u8be5\u5b57\u7b26\u4e32\u768432\u4f4dMD5\uff1a`E903???4DAB????08?????51?80??8A?`\uff08\u90e8\u5206\u5b57\u7b26\u5df2\u77e5\uff09\n\u76ee\u6807\uff1a\u627e\u51fa\u539f\u59cb\u5b57\u7b26\u4e32\uff0c\u5e76\u63d0\u4ea4\u5176\u5b8c\u6574MD5\u503c\u4f5c\u4e3aflag<\/code><\/pre>\n\n\n\n<p><strong>\u89e3\u9898\u601d\u8def<\/strong><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\u67093\u4e2a\u672a\u77e5\u5927\u5199\u5b57\u6bcd\uff0c\u603b\u5171\u6709 26\u00b3 = 17,576 \u79cd\u53ef\u80fd\u7ec4\u5408\n\u901a\u8fc7\u66b4\u529b\u679a\u4e3e\u6240\u6709\u53ef\u80fd\u7684\u7ec4\u5408\n\u5bf9\u6bcf\u4e2a\u7ec4\u5408\u8ba1\u7b97MD5\u503c\uff0c\u68c0\u67e5\u662f\u5426\u4e0e\u5df2\u77e5\u6a21\u5f0f\u5339\u914d\n\u627e\u5230\u5339\u914d\u7684\u5b57\u7b26\u4e32\uff0c\u83b7\u53d6\u5176\u5b8c\u6574MD5\u503c<\/code><\/pre>\n\n\n\n<p>py\u811a\u672c<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>import hashlib\nimport itertools\nimport string\n\n# \u57fa\u7840\u5b57\u7b26\u4e32\u6a21\u677f\nbase_str = \"TASC{}O3RJMV{}WDJKX{}ZM\"\n# MD5\u6a21\u5f0f\uff08\u5927\u5199\uff09\nmd5_pattern = \"E903???4DAB????08?????51?80??8A?\"\n\ndef matches_pattern(computed_md5, pattern):\n    \"\"\"\u68c0\u67e5\u8ba1\u7b97\u7684MD5\u662f\u5426\u5339\u914d\u7ed9\u5b9a\u6a21\u5f0f\"\"\"\n    if len(computed_md5) != len(pattern):\n        return False\n\n    for c1, c2 in zip(computed_md5, pattern):\n        if c2 != '?' and c1 != c2:\n            return False\n    return True\n\n# \u679a\u4e3e\u6240\u6709\u53ef\u80fd\u7684\u5927\u5199\u5b57\u6bcd\u7ec4\u5408\nfor combo in itertools.product(string.ascii_uppercase, repeat=3):\n    test_str = base_str.format(combo&#91;0], combo&#91;1], combo&#91;2])\n    md5_hash = hashlib.md5(test_str.encode()).hexdigest().upper()\n\n    if matches_pattern(md5_hash, md5_pattern):\n        print(f\"\u539f\u59cb\u5b57\u7b26\u4e32: {test_str}\")\n        print(f\"\u5b8c\u6574MD5: {md5_hash}\")\n        print(f\"flag{{ {md5_hash} }}\")  # \u63d0\u4ea4\u7b54\u6848\u683c\u5f0f\n        break<\/code><\/pre>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-481.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"956\" height=\"245\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-481.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2065\"  sizes=\"auto, (max-width: 956px) 100vw, 956px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{E9032994DABAC08080091151380478A2}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">30.\u5f02\u6027\u76f8\u5438<\/h2>\n\n\n\n<p>key:asadsasdasdasdasdasdasdasdasdasdqwesqf<\/p>\n\n\n\n<p>\u5bc6\u6587\uff1a\u071f\u0804\u1255\u0310\u5458\u4b5c\u584a\u5653\u4452\u0344\u0258\u4606\u5447\u0556\u4757\u4412\u5d4a\u141b<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\u6709\u4e24\u4e2a\u6587\u4ef6\uff1akey.txt \u548c \u5bc6\u6587.txt\n\u4e24\u8005\u5185\u5bb9\u5747\u4e3a\uff1a`asadsasdasdasdasdasdasdasdasdasdqwesqf`\n\u9898\u76ee\u8981\u6c42\u8bc1\u660e\"\u5f02\u6027\u76f8\u5438\"\u7684\u6b63\u786e\u6027\n\u5728\u5bc6\u7801\u5b66\u4e2d\uff0c\"\u5f02\u6027\u76f8\u5438\"\u5e38\u6307XOR(\u5f02\u6216)\u64cd\u4f5c\u7684\u7279\u6027\uff1a0\u548c1(\u5f02\u6027)\u8fdb\u884cXOR\u8fd0\u7b97\u4f1a\u5f97\u52301(\u76f8\u5438)<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code>\u9898\u76ee\u6697\u793a\u4f7f\u7528XOR(\u5f02\u6216)\u64cd\u4f5c\u8fdb\u884c\u89e3\u5bc6\u5728XOR\u52a0\u5bc6\u4e2d\uff0c\u660e\u6587 XOR \u5bc6\u94a5 = \u5bc6\u6587\u56e0\u6b64\uff0c\u5bc6\u6587 XOR \u5bc6\u94a5 = \u660e\u6587\uff0c\u867d\u7136\u4e24\u4e2a\u6587\u4ef6\u5185\u5bb9\u76f8\u540c\uff0c\u4f46\u5b9e\u9645\u6311\u6218\u4e2d\u5b83\u4eec\u5e94\u8be5\u662f\u4e0d\u540c\u7684\u7f16\u5199\u4e00\u4e2a\u901a\u7528XOR\u89e3\u5bc6\u811a\u672c\nXOR(\u5f02\u6216)\u64cd\u4f5c\uff1a\u5f53\u4e24\u4e2a\u4f4d\u4e0d\u540c\u65f6\u7ed3\u679c\u4e3a1\uff08\u5f02\u6027\u76f8\u5438\uff09\uff0c\u76f8\u540c\u65f6\u7ed3\u679c\u4e3a0\nXOR\u7279\u6027\uff1a(A XOR B) XOR B = A\uff0c\u8fd9\u4f7f\u5176\u6210\u4e3a\u5b8c\u7f8e\u7684\u52a0\u5bc6\/\u89e3\u5bc6\u64cd\u4f5c\n\u5b9e\u9645\u5e94\u7528\uff1a\u5728\u672c\u9898\u4e2d\uff0c\u5bc6\u6587\u4e0e\u5bc6\u94a5\u8fdb\u884cXOR\u64cd\u4f5c\uff0c\u6062\u590d\u539f\u59cb\u660e\u6587\n\"\u5f02\u6027\u76f8\u5438\"\u7684\u79d1\u5b66\u6027\uff1a\u5728\u7269\u7406\u5b66\u4e2d\uff0c\u5f02\u6027\u7535\u8377\u76f8\u5438\u662f\u57fa\u672c\u89c4\u5f8b\uff0c\u6b63\u5982XOR\u64cd\u4f5c\u4e2d0\u548c1\u7684\"\u5438\u5f15\"\u7279<\/code><\/pre>\n\n\n\n<p>py3\u811a\u672c<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code># \u8bfb\u53d6\u5bc6\u94a5\u548c\u5bc6\u6587\nwith open('key.txt', 'r') as f:\n    key = f.read().strip()\n\nwith open('\u5bc6\u6587.txt', 'r') as f:\n    ciphertext = f.read().strip()\n\n# \u5c06\u5b57\u7b26\u4e32\u8f6c\u6362\u4e3a\u5b57\u8282\nkey_bytes = key.encode('utf-8')\ncipher_bytes = ciphertext.encode('utf-8')\n\n# \u786e\u4fdd\u5bc6\u94a5\u957f\u5ea6\u4e0e\u5bc6\u6587\u76f8\u540c\uff08\u91cd\u590d\u5bc6\u94a5\uff09\nkey_bytes = (key_bytes * (len(cipher_bytes) \/\/ len(key_bytes) + 1))&#91;:len(cipher_bytes)]\n\n# \u6267\u884cXOR\u64cd\u4f5c\u89e3\u5bc6\nplaintext_bytes = bytes(&#91;cipher_bytes&#91;i] ^ key_bytes&#91;i] for i in range(len(cipher_bytes))])\nplaintext = plaintext_bytes.decode('utf-8', errors='ignore')\n\nprint(f\"\u89e3\u5bc6\u7ed3\u679c: {plaintext}\")\nprint(f\"flag{{{plaintext}}}\")<\/code><\/pre>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-482.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"855\" height=\"210\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-482.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2066\"  sizes=\"auto, (max-width: 855px) 100vw, 855px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{ea1bc0988992276b7f95b54a7435e89e}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">31.RSA<\/h2>\n\n\n\n<p>\u516c\u94a5\uff08Public Key\uff09\u7ecf\u8fc7\u89e3\u6790\u540e\uff0c\u53ef\u4ee5\u53d1\u73b0\u5176\u6a21\u6570 $N$ \u975e\u5e38\u5c0f\u3002<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u7b97\u6cd5<\/strong>: RSA<\/li>\n\n\n\n<li><strong>\u6a21\u6570 ($N$) \u957f\u5ea6<\/strong>: 256 \u4f4d (Bits)<\/li>\n\n\n\n<li><strong>\u5b89\u5168\u9690\u60a3<\/strong>: \u73b0\u4ee3 RSA \u901a\u5e38\u4f7f\u7528 2048 \u4f4d\u6216 4096 \u4f4d\u3002256 \u4f4d\u7684 RSA \u5bc6\u94a5\u5728\u73b0\u4ee3\u8ba1\u7b97\u673a\u4e0a\u53ef\u4ee5\u5728\u51e0\u79d2\u949f\u5185\u5b8c\u6210\u56e0\u6570\u5206\u89e3\uff0c\u4ece\u800c\u7b97\u51fa\u79c1\u94a5\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>\u63d0\u53d6\u516c\u94a5\u4fe1\u606f: \u4ece PEM \u5b57\u7b26\u4e32\u4e2d\u63d0\u53d6\u6a21\u6570 $N$ \u548c\u6307\u6570 $e$\u3002\n\u5206\u89e3\u6a21\u6570 $N$: \u4f7f\u7528\u5de5\u5177\uff08\u5982 factordb\uff09\u5c06 $N$ \u5206\u89e3\u4e3a\u4e24\u4e2a\u7d20\u6570 $p$ \u548c $q$\u3002\n\u8ba1\u7b97\u79c1\u94a5 $d$: \u6839\u636e\u516c\u5f0f $d equiv e^{-1} pmod{(p-1)(q-1)}$ \u8ba1\u7b97\u79c1\u94a5\u3002\n\u89e3\u5bc6: \u8bfb\u53d6 `flag.enc`\uff0c\u5c06\u5176\u8f6c\u6362\u4e3a\u6574\u6570\uff0c\u4f7f\u7528\u79c1\u94a5\u8fdb\u884c\u89e3\u5bc6\u8fd0\u7b97 $m equiv c^d pmod N$\uff0c\u6700\u540e\u8f6c\u56de\u6587\u672c\u3002<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code>import base64\nfrom Crypto.PublicKey import RSA\nfrom Crypto.Util.number import bytes_to_long, long_to_bytes, inverse\nimport requests\nimport re\n\n# 1. \u8bbe\u7f6e\u516c\u94a5\u548c\u5bc6\u6587\u6587\u4ef6\npub_key_pem = \"\"\"-----BEGIN PUBLIC KEY-----\nMDwwDQYJKoZIhvcNAQEBBQADKwAwKAIhAMAzLFxkrkcYL2wch21CM2kQVFpY9+7+\n\/AvKr1rzQczdAgMBAAE=\n-----END PUBLIC KEY-----\"\"\"\n\nfilename = \"flag.enc\"\n\ndef solve():\n    print(\"&#91;*] \u6b63\u5728\u89e3\u6790\u516c\u94a5...\")\n    key = RSA.importKey(pub_key_pem)\n    n = key.n\n    e = key.e\n    print(f\"    n = {n}\")\n    print(f\"    e = {e}\")\n    print(f\"    n \u7684\u4f4d\u6570\u4e3a: {n.bit_length()} (256\u4f4d\u662f\u975e\u5e38\u5bb9\u6613\u7834\u89e3\u7684)\")\n\n    # 2. \u5206\u89e3 N (\u4f7f\u7528 factordb API)\n    print(\"n&#91;*] \u6b63\u5728\u67e5\u8be2 FactorDB \u5206\u89e3 N...\")\n    try:\n        api_url = f\"http:\/\/factordb.com\/api?query={n}\"\n        response = requests.get(api_url)\n        data = response.json()\n\n        # \u68c0\u67e5\u662f\u5426\u5206\u89e3\u6210\u529f (status 'FF' \u8868\u793a\u5b8c\u5168\u5206\u89e3)\n        if data&#91;'status'] != 'FF' and data&#91;'status'] != 'CF':\n            print(\"&#91;-] FactorDB \u672a\u627e\u5230\u73b0\u6210\u56e0\u5b50\uff0c\u53ef\u80fd\u9700\u8981\u4f7f\u7528 yafu \u672c\u5730\u8dd1\u4e00\u4e0b\u3002\")\n            print(f\"\u8bf7\u624b\u52a8\u5206\u89e3\u8fd9\u4e2a\u6570\u5b57: {n}\")\n            return\n\n        factors = data&#91;'factors']\n        # factordb \u8fd4\u56de\u7684\u662f &#91;\u56e0\u5b50, \u6b21\u6570]\uff0c\u6211\u4eec\u9700\u8981\u63d0\u53d6 p \u548c q\n        # \u5bf9\u4e8e RSA\uff0c\u901a\u5e38\u662f\u4e24\u4e2a\u7d20\u6570\uff0c\u6240\u4ee5\u5217\u8868\u5e94\u8be5\u5305\u542b\u4e24\u4e2a\u4e0d\u540c\u7684\u7d20\u6570\uff0c\u6216\u8005\u4e00\u4e2a\u7d20\u6570\u51fa\u73b0\u4e24\u6b21\n        prime_factors = &#91;]\n        for f in factors:\n            val = int(f&#91;0])\n            count = int(f&#91;1])\n            for _ in range(count):\n                prime_factors.append(val)\n\n        if len(prime_factors) != 2:\n            print(\"&#91;-] \u56e0\u5b50\u6570\u91cf\u5f02\u5e38\uff0c\u4e0d\u662f\u6807\u51c6\u7684 p * q RSA\u3002\")\n            return\n\n        p = prime_factors&#91;0]\n        q = prime_factors&#91;1]\n        print(f\"    p = {p}\")\n        print(f\"    q = {q}\")\n\n    except Exception as err:\n        print(f\"&#91;-] \u7f51\u7edc\u67e5\u8be2\u5931\u8d25: {err}\")\n        print(\"\u8bf7\u624b\u52a8\u4f7f\u7528\u5de5\u5177\u5206\u89e3 N\u3002\")\n        return\n\n    # 3. \u8ba1\u7b97\u79c1\u94a5 d\n    print(\"n&#91;*] \u8ba1\u7b97\u79c1\u94a5 d...\")\n    phi = (p - 1) * (q - 1)\n    d = inverse(e, phi)\n    print(f\"    d = {d}\")\n\n    # 4. \u89e3\u5bc6\u6587\u4ef6\n    print(\"n&#91;*] \u6b63\u5728\u89e3\u5bc6 flag.enc ...\")\n    try:\n        with open(filename, \"rb\") as f:\n            ciphertext = f.read()\n            c_int = bytes_to_long(ciphertext)\n\n            # RSA \u89e3\u5bc6\u516c\u5f0f: m = c^d mod n\n            m_int = pow(c_int, d, n)\n\n            flag = long_to_bytes(m_int)\n            print(\"n\" + \"=\"*30)\n            print(f\"FLAG: {flag.decode('utf-8', errors='ignore')}\")\n            print(\"=\"*30 + \"n\")\n\n    except FileNotFoundError:\n        print(f\"&#91;-] \u9519\u8bef: \u627e\u4e0d\u5230\u6587\u4ef6 {filename}\uff0c\u8bf7\u786e\u4fdd\u5b83\u5728\u5f53\u524d\u76ee\u5f55\u4e0b\u3002\")\n    except Exception as e:\n        print(f\"&#91;-] \u89e3\u5bc6\u8fc7\u7a0b\u4e2d\u51fa\u9519: {e}\")\n\nif __name__ == \"__main__\":\n    solve()\n<\/code><\/pre>\n\n\n\n<figure class=\"wp-block-image size-large\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-483-1024x421.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"421\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-483-1024x421.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2067\"  sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{decrypt_256}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">32.RSAROLL<\/h2>\n\n\n\n<p>data.txt<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>{920139713,19}\n\n704796792\n752211152\n274704164\n18414022\n368270835\n483295235\n263072905\n459788476\n483295235\n459788476\n663551792\n475206804\n459788476\n428313374\n475206804\n459788476\n425392137\n704796792\n458265677\n341524652\n483295235\n534149509\n425392137\n428313374\n425392137\n341524652\n458265677\n263072905\n483295235\n828509797\n341524652\n425392137\n475206804\n428313374\n483295235\n475206804\n459788476\n306220148\n<\/code><\/pre>\n\n\n\n<p>\u9898\u76ee.txt<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>RSA roll\uff01roll\uff01roll\uff01\nOnly number and a-z\n\uff08don't use editor\nwhich MS provide\uff09<\/code><\/pre>\n\n\n\n<p><strong>\u5bc6\u94a5\u751f\u6210\uff1a<\/strong><\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><br><p>\u9009\u62e9\u4e24\u4e2a\u5927\u7d20\u6570 p \u548c q<\/p><br><\/li>\n\n\n\n<li><br><p>\u8ba1\u7b97 n = p \u00d7 q<\/p><br><\/li>\n\n\n\n<li><br><p>\u8ba1\u7b97 \u03c6(n) = (p-1)(q-1)<\/p><br><\/li>\n\n\n\n<li><br><p>\u9009\u62e9 e\uff081&lt;e&lt;\u03c6(n)\uff0c\u4e14\u4e0e \u03c6(n) \u4e92\u8d28\uff09<\/p><br><\/li>\n\n\n\n<li><br><p>\u8ba1\u7b97 d \u2261 e\u207b\u00b9 mod \u03c6(n)<\/p><br><\/li>\n\n\n\n<li><br><p><strong>\u5df2\u77e5\u53c2\u6570\uff1a<\/strong> n=920139713\uff0ce=19\uff0c\u5bc6\u6587\u5217\u8868<\/p><br><\/li>\n\n\n\n<li><br><p><strong>\u5206\u89e3 n\uff1a<\/strong> n = 18443 \u00d7 49891\uff08p=18443\uff0cq=49891\uff09<\/p><br><\/li>\n\n\n\n<li><br><p><strong>\u8ba1\u7b97 \u03c6(n)\uff1a<\/strong> \u03c6(n) = 18442 \u00d7 49890 = 920071380<\/p><br><\/li>\n\n\n\n<li><br><p><strong>\u6c42\u79c1\u94a5 d\uff1a<\/strong> d \u2261 19\u207b\u00b9 mod \u03c6(n) = 96849619<\/p><br><\/li>\n\n\n\n<li><br><p><strong>\u89e3\u5bc6\u8fd0\u7b97\uff1a<\/strong> \u5bf9\u6bcf\u4e2a\u5bc6\u6587 c \u8ba1\u7b97 c\u2079\u2076\u2078\u2074\u2079\u2076\u00b9\u2079 mod 920139713<\/p><br><\/li>\n\n\n\n<li><br><p><strong>\u8f6c\u5b57\u7b26\uff1a<\/strong> \u5c06\u89e3\u5bc6\u7ed3\u679c\u4f5c\u4e3a ASCII \u7801\u8f6c\u4e3a\u5b57\u7b26<\/p><br><\/li>\n<\/ol>\n\n\n\n<p>py3\u89e3\u9898\u811a\u672c<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>import sys\n\n# \u6269\u5c55\u6b27\u51e0\u91cc\u5f97\u7b97\u6cd5\u6c42\u6a21\u9006\ndef egcd(a, b):\n    if b == 0:\n        return (1, 0, a)\n    else:\n        x, y, g = egcd(b, a % b)\n        return (y, x - (a \/\/ b) * y, g)\n\n# RSA \u89e3\u5bc6\u51fd\u6570\ndef rsa_decrypt(ciphertext, d, n):\n    return pow(ciphertext, d, n)\n\ndef main():\n    # \u8bfb\u53d6\u6587\u4ef6\n    with open('data.txt', 'r') as f:\n        lines = f.readlines()\n\n    # \u89e3\u6790\u7b2c\u4e00\u884c\u83b7\u53d6 N \u548c e\n    first_line = lines&#91;0].strip()\n    # \u53bb\u9664\u82b1\u62ec\u53f7\n    first_line = first_line.strip('{}')\n    n_str, e_str = first_line.split(',')\n    n = int(n_str)\n    e = int(e_str)\n\n    # \u5df2\u77e5\u7684\u8d28\u56e0\u6570 p \u548c q\uff08\u901a\u8fc7\u5206\u89e3 N \u5f97\u5230\uff09\n    p = 18443\n    q = 49891\n\n    # \u9a8c\u8bc1 p*q \u662f\u5426\u7b49\u4e8e N\n    if p * q != n:\n        print(\"\u9519\u8bef\uff1ap*q \u4e0d\u7b49\u4e8e N\")\n        sys.exit(1)\n\n    # \u8ba1\u7b97 \u03c6(N)\n    phi = (p - 1) * (q - 1)\n\n    # \u8ba1\u7b97\u79c1\u94a5 d\uff08e \u6a21 \u03c6(N) \u7684\u9006\u5143\uff09\n    # \u4f7f\u7528\u6269\u5c55\u6b27\u51e0\u91cc\u5f97\u7b97\u6cd5\n    d, _, g = egcd(e, phi)\n    if g != 1:\n        print(\"\u9519\u8bef\uff1ae \u548c \u03c6(N) \u4e0d\u4e92\u8d28\")\n        sys.exit(1)\n\n    # \u786e\u4fdd d \u662f\u6b63\u6570\n    d = d % phi\n    if d &lt; 0:\n        d += phi\n\n    # \u8bfb\u53d6\u5bc6\u6587\uff08\u4ece\u7b2c\u4e8c\u884c\u5f00\u59cb\uff09\n    ciphertexts = &#91;]\n    for line in lines&#91;1:]:\n        line = line.strip()\n        if line:  # \u8df3\u8fc7\u7a7a\u884c\n            ciphertexts.append(int(line))\n\n    # \u89e3\u5bc6\u6bcf\u4e2a\u5bc6\u6587\n    plaintext_chars = &#91;]\n    for ct in ciphertexts:\n        # RSA \u89e3\u5bc6\n        pt_num = rsa_decrypt(ct, d, n)\n        # \u5c06\u89e3\u5bc6\u540e\u7684\u6570\u5b57\u8f6c\u6362\u4e3a ASCII \u5b57\u7b26\n        # \u6ce8\u610f\uff1a\u6bcf\u4e2a\u89e3\u5bc6\u7ed3\u679c\u5e94\u8be5\u662f\u4e00\u4e2a\u5b57\u8282\uff080-255\uff09\n        if pt_num &lt; 0 or pt_num &gt; 255:\n            print(f\"\u8b66\u544a\uff1a\u89e3\u5bc6\u540e\u7684\u503c {pt_num} \u8d85\u51fa ASCII \u8303\u56f4\")\n        else:\n            plaintext_chars.append(chr(pt_num))\n\n    # \u62fc\u63a5\u6240\u6709\u5b57\u7b26\u5f97\u5230 flag\n    flag = ''.join(plaintext_chars)\n    print(\"\u89e3\u5bc6\u540e\u7684 flag \u4e3a\uff1a\")\n    print(flag)\n\nif __name__ == \"__main__\":\n    main()<\/code><\/pre>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-484.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"820\" height=\"105\" data-original=\"https:\/\/www.sanjiuctf.cn\/wp-content\/uploads\/2025\/12\/image-484.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-2068\"  sizes=\"auto, (max-width: 820px) 100vw, 820px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-code\"><code>flag{13212je2ue28fy71w8u87y31r78eu1e2}<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"<p>1.\u4e00\u773c\u5c31\u89e3\u5bc6 base64\u89e3\u7801 2.MD5 MD5\u5728\u7ebf\u89e3\u5bc6\u5c31\u884c 3.Url\u7f16\u7801 4.\u770b\u6211\u56de\u65cb\u8e22 Rot13\u89e3 [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[21,9],"tags":[],"class_list":["post-2004","post","type-post","status-publish","format-standard","hentry","category-buuctf","category-wp"],"_links":{"self":[{"href":"https:\/\/www.sanjiuctf.cn\/index.php?rest_route=\/wp\/v2\/posts\/2004","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.sanjiuctf.cn\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.sanjiuctf.cn\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.sanjiuctf.cn\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.sanjiuctf.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=2004"}],"version-history":[{"count":1,"href":"https:\/\/www.sanjiuctf.cn\/index.php?rest_route=\/wp\/v2\/posts\/2004\/revisions"}],"predecessor-version":[{"id":2069,"href":"https:\/\/www.sanjiuctf.cn\/index.php?rest_route=\/wp\/v2\/posts\/2004\/revisions\/2069"}],"wp:attachment":[{"href":"https:\/\/www.sanjiuctf.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2004"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.sanjiuctf.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2004"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.sanjiuctf.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2004"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}