CSAW Quals 2016 :: Neo :: Crypto 200

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We start out with just a link and a bit of text, the link points to http://crypto.chal.csaw.io:8001 – though this probably won’t live forever. Once you go to the page, you would probably notice a few things Looks like it’s from the early xp era Seems to be centered around some movie that it’s named… Read more »

CSAW Qual 2016::Rock::Rev-100

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There is a struct in this program. Three interesting functions, which I have called init_struct, check_len_and_xor, and is_valid_key See the rest of this writeup here.

CSAW Qual 2016::Warmup::Pwn-50

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This was a very easy challenge. Basically, there was a win function at the address that is bring printed : 0x40060D. This function can be called with a simple buffer overflow. Here is my Exploit.py Which gave me the flag View the original post here.

CSAW Qual 2016::Sleeping Guard::Crypto-50

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With this challenge, they gave us an encrypted png. After a bit of trial and error I realized all I had to do was xor the first few bytes of the encrypted file with the standard header of a png. I just downloaded a sample file. Here is my get_key.py Which gave me the… Read more »