题目链接:https://adworld.xctf.org.cn/task/task_list?type=misc&number=1&grade=1&page=4
用winhex分析文件发现是rar文件
该后缀名为rar进行解压
扔进winhex发现是流量包 用wireshark打开
追踪TCP流,在第5个tcp流中发现flag.rar
导出对象
解压flag.rar 发现需要密码
解压要密码
在第6个TCP流中发现一些linux指令 一个base64 一段python
base64:19aaFYsQQKr+hVX6hl2smAUQ5a767TsULEUebWSajEo=
python代码
# coding:utf-8
__author__ = 'YFP'
from Crypto import Random
from Crypto.Cipher import AES
import sys
import base64
IV = 'QWERTYUIOPASDFGH'
def decrypt(encrypted):
aes = AES.new(IV, AES.MODE_CBC, IV)
return aes.decrypt(encrypted)
def encrypt(message):
length = 16
count = len(message)
padding = length - (count % length)
message = message + '\0' * padding
aes = AES.new(IV, AES.MODE_CBC, IV)
return aes.encrypt(message)
str = 'this is a test'
example = encrypt(str)
print(decrypt(example))
进行解密
# coding:utf-8
__author__ = 'YFP'
from Crypto import Random
from Crypto.Cipher import AES
import sys
import base64
IV = 'QWERTYUIOPASDFGH'
def decrypt(encrypted):
aes = AES.new(IV, AES.MODE_CBC, IV)
return aes.decrypt(encrypted)
def encrypt(message):
length = 16
count = len(message)
padding = length - (count % length)
message = message + '\0' * padding
aes = AES.new(IV, AES.MODE_CBC, IV)
return aes.encrypt(message)
str = 'this is a test'
example = encrypt(str)
print(decrypt(example))
s='19aaFYsQQKr+hVX6hl2smAUQ5a767TsULEUebWSajEo='
flag=base64.b64decode(s)
print(decrypt(flag))
得到密码passwd={No_One_Can_Decrypt_Me}
flag:WDCTF{Seclab_CTF_2017}