某建筑网页：

网站：

import base64
# 解码
website = base64.b64decode('aHR0cHM6Ly9qenNjLm1vaHVyZC5nb3YuY24vZGF0YS9jb21wYW55'.encode('utf-8'))
print(website)

JSON.parse()

​ 当你有一个包含JSON字符串的变量时，你可以使用JSON.parse()将其转换为JavaScript对象。

var jsonString = '{"name":"John","age":30,"city":"New York"}';
var jsonObject = JSON.parse(jsonString);
console.log(jsonObject.name); // 输出：John
console.log(jsonObject.age);  // 输出：30
console.log(jsonObject.city); // 输出：New York

思路：

表单中都是正常数据，没有特殊的数据。

相应是密文：

JSON.parse 进行初步尝试搜素

d.a 就是CryptoJS的一个对象，使用标准库替换即可

但是会报错。

我们可以思考一下哪里错了，第一密文数据肯定没有错，有错的话就是iv值，密钥有一些问题。

我们的密钥与网页的不一样啊！

没办法，在加个断点呗。

注意上面我打断点的位置，在这个解密函数这行打上断点，这行之前应该iv和密钥已经被确定了。

对比一下，发现密钥f的值有变换，说明f被覆盖了。我需要使用覆盖后的。

然后我添加一个监听器

会发现，f在解密之前已经生成好了，而且优先级很高，没有被后面那个f覆盖。

将其转化为字符串全局搜索看看吧。

关于iv和key变不变的问题，就看他每一次有没有发送性的请求，没有的话就是固定的

js代码：

const CryptoJS = require("crypto-js");
f =CryptoJS .enc.Utf8.parse("Dt8j9wGw%6HbxfFn")
m = CryptoJS .enc.Utf8.parse("0123456789ABCDEF");
function b(t) {
var e = CryptoJS .enc.Hex.parse(t)
, n = CryptoJS .enc.Base64.stringify(e)
, a = CryptoJS .AES.decrypt(n, f, {
            iv: m,
            mode: CryptoJS .mode.CBC,
            padding: CryptoJS .pad.Pkcs7
})
, r = a.toString(CryptoJS .enc.Utf8);
return    r.toString()
}

data='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console.log(b(data))

function AesDecrypt(Key,Iv,text) {
    var key = CryptoJS.enc.Utf8.parse(Key),
        iv = CryptoJS.enc.Utf8.parse(Iv),
        srcs = text,
        // CBC 加密方式，Pkcs7 填充方式
        decrypted = CryptoJS.AES.decrypt(srcs, key, {
            iv: iv,
            mode: CryptoJS.mode.CBC,
            padding: CryptoJS.pad.Pkcs7
        });
    return decrypted.toString(CryptoJS.enc.Utf8);
}