[InCTF 2021]Tabula Recta
| ID： | 13746 |
|---|---|
| 标题： | [InCTF 2021]Tabula Recta |
| 描述： | X made a stateless password manager and used it for all the top sites he visited. But on observing the code he found that his key could retrieve a maximum number of states and decided to not use it because of its weaknesses. However, he did not get to reset all of his passwords. 得到的flag请使用NSSCTF{}格式提交。 本题最终只需要提交得到的Master Key即可。 |
| 类型： | crypto |
| 网站： | NSSCTF |
| 题目链接： | https://www.nssctf.cn/problem/226 |
| 赛事： | InCTF |
| 年度： | 2021 |
| Flag值： | 无 |
| writeup： |
https://blog.bi0s.in/2021/08/20/Crypto/Tabula-Recta-InCTF-Internationals-2021/ 验证后的网址：该链接为bi0s团队发布的官方Writeup，详细描述了通过矩阵运算恢复RC4弱密钥生成算法中的表项，利用b-exact key特性逆向密码表并最终获取flag的完整过程。文中明确提到"Reversing the given password using simple Matrix operations would give the first 12 output bytes of the cipher"等关键步骤，与CTFtime.org的writeup内容一致，验证过程逻辑严密且包含具体技术细节。 |