从一道CTF题实战Python暴力破解AES-ECB加密的完整指南1. 题目背景与加密原理分析这道CTF题目提供了一个AES-ECB模式的加密函数和一个被加密的flag.txt文件。我们先来看加密函数的实现import Crypto import PTL import base64 txt flag # 待加密的flag def aes(txt): data txt.encode(utf-8) key random.randint(100000, 999999) key str(key) str(key) str(key)[0:4] data data It is real flag! cipher AES.new(key, AES.MODE_ECB) ct_bytes cipher.encrypt(data) return ct_bytes print(aes(txt))关键加密特点分析使用AES-ECB模式加密密钥生成方式取6位随机数重复拼接两次后加前4位形成16字节密钥明文在flag后追加固定字符串It is real flag!输出base64编码的加密结果2. ECB模式的安全弱点AES-ECB电子密码本模式的主要安全问题相同明文块产生相同密文块ECB模式下相同的明文块会被加密成相同的密文块缺乏扩散性错误不会传播到其他块容易遭受重放攻击攻击者可以交换密文块针对本题的利用点已知明文It is real flag!的存在可以作为已知明文攻击的突破口密钥空间有限100000-999999可暴力破解3. 破解脚本编写实战以下是完整的Python破解脚本from Cryptodome.Cipher import AES import base64 # 已知的加密后flag encrypted_flag 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