Crypto 10

Crypto 10¶

📚 Category: Crypto
🎯 Points: 300
📝 Description: Use flagCheck to input the flag you get from the challenge to get the actual flag

✍️ Writeup¶

We one file:

chall.txt

Cipher text: LQBN XBEE IG HWV EDNL LVDCNSBNNBHC. ZHW'MG DEE VGKGBMGO ZHWV DNNBPCSGCLN. BA ZHW DVG DIEG LH KHSTEGLG ZHWV LDNR VGTEZ IDKR LH WN WNBCP LQG RGZXHVO AVHS LQBN GCKVZTLBHC DEPHVBLQS DN ZHWV RGZ. JWNL VGSGSIGV LQDL LQBN BN DEE AHV LQG PVGDLGV PHHO.

This is a Monoalphabetic Substitution Cipher

ABCDEFGHIJKLMNOPQRSTUVWXYZ
finalzeobjctvsdghkmpqruwxy

THIS WILL BE OUR LAST TRANSMISSION. YOU'VE ALL RECEIVED YOUR ASSIGNMENTS. IF YOU ARE ABLE TO COMPLETE YOUR TASK REPLY BACK TO US USING THE KEYWORD FROM THIS ENCRYPTION ALGORITHM AS YOUR KEY. JUST REMEMBER THAT THIS IS ALL FOR THE GREATER GOOD.

Let's check with `flagCheck`

hacker@csawctf2011~crypto-300-8:/challenge$ ./flagCheck Enter the flag: finalzeobjctvsdghkmpqruwxy Correct flag! pwn.college{REDACTED} ```