秃头逆向刷题21-4-27

Shuffle

Source : XCTF

FIle : Click

Hint : 找到字符串在随机化之前.

Check the shell with Exeinfo :

This is an ELF file , and no shell.

Drop it into IDA32 , Shift + F12 to check string :

It’s obviously ASCII code, and it starts with flag:

Select ASCII code, press R to switch to string:

flag get!

SECCON{Welcome to the SECCON 2014 CTF!}

answer_to_everything

Type : REV

File : Click

Hint : sha1 得到了一个神秘的二进制文件。寻找文件中的flag，解锁宇宙的秘密。注意：将得到的 flag变为flag{XXX}形式提交。

It must be easy , don’t have shell;

Gdb:

Given is the flag, but no matter how to submit is wrong;

Go back to the prompt and think about it carefully, and find that SHA1 encryption is given;

Let’s having a try:

That’s right ! flag get!

flag{80ee2a3fe31da904c596d993f7f1de4827c1450a}