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每日一题 —— [PolarCTF]召唤神龙

题目地址:https://www.polarctf.com/#/page/challenges

打开题目,是一个前些年突然爆火的小游戏 —— 召唤神龙。先进去玩了一圈, 被吃了.

可以看到,这个是一个纯前端的小游戏,也就是说所有信息都是在“源代码”这一栏找就可以。但是刚进去的时候,F12 没有反应,可以知道这个网页禁止了你打开 devtools 控制台。我们可以用最简单的方法绕过:先打开另一个网页,按下 F12 ,然后将上面的地址栏里的地址替换成题目地址,就可以对这题目打开控制台了。注意这个时候你就不能再关闭控制台了,否则你就得重复以上的步骤

然后动用我们的全局搜索的功能,在“源代码”这一栏里开始全局搜索,比如说 polarctf flag{ 之类的,但是并没有什么效果。

然后我们排查各种 js 文件,最后发现在 main.js 里面,注释掉了一行特别明显的经过混淆的 js 代码。由一对中括号小括号组成:

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这个东西我是知道它是 js 混淆的,但是上一次遇到他的时候并不知道它的名字,而问的 AI 也不知道,所以上一次就没做出来。这一次经过查询资料,知道这种方法叫做 JSFuck ,也就是说我们把他丢进 JSFuck 的解密网站就可以得到内容了。

随便找到一个解密网站,把这个玩意丢进去,就看到了 flag.


另外,由于这一串玩意是正宗的 js 代码,把它直接往 devtools 的控制台丢并运行,也可以得到 flag。 既然知道这玩意叫什么了,那么我得去看一下之前遗留下来的另一道题了。


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