picoCTF 2022: Crypto – rail-fence

Ulli Weichert/ April 3, 2022/ IT-Security, Write-Ups/ 0Kommentare

rail-fence Description A type of transposition cipher is the rail fence cipher, which is described here. Here is one such cipher encrypted using the rail fence with 4 rails. Can you decrypt it? Download the message here. Put the decoded message in the picoCTF flag format, picoCTF{decoded_message}. Solving So – there is everything we need to know in the challenge

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picoCTF 2022: Crypto – Diffie Hellman

Ulli Weichert/ April 3, 2022/ IT-Security, Write-Ups/ 0Kommentare

diffie-hellman Description Alice and Bob wanted to exchange information secretly. The two of them agreed to use the Diffie-Hellman key exchange algorithm, using p = 13 and g = 5. They both chose numbers secretly where Alice chose 7 and Bob chose 3. Then, Alice sent Bob some encoded text (with both letters and digits) using the generated key as

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picoCTF 2022: Crypto – Morse Code

Ulli Weichert/ April 3, 2022/ IT-Security, Write-Ups/ 0Kommentare

morse-code Description Morse code is well known. Can you decrypt this? Download the file here. Wrap your answer with picoCTF{}, put underscores in place of pauses, and use all lowercase. Solving The soundfile is a morse code You could either translate it by your self with the morse alphabet or use this link Change all characters to lowercase and replace

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TheFewChosen CTF 2021: Forensics – Ocean / Writeup

Ulli Weichert/ November 28, 2021/ IT-Security, Write-Ups/ 0Kommentare

OCEAN What can you do in an ocean of files? nc server.challenge.ctf.thefewchosen.com 1338 Hints There is an official hint: Hint for ocean: The chal file is not relevant. That’s just a shell (basically the entrypoint). Try listing folders and subfolders Todos So we looked around for a while and found this directory (Magic trick was to use ls -R instead

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K3RN3L CTF 2021: Kiddie Pool – 3in1 / Writeup

Ulli Weichert/ November 14, 2021/ hacking, IT-Security, Write-Ups/ 0Kommentare

3in1 Description Like Nescafeeeee! Attachments https://ctf.k3rn3l4rmy.com/kernelctf-distribution-challs/nescafeee/AES.py Todos To decrypt the string in the given AES.py script (String is in scriptfile as a comment). from Crypto.Cipher import AES from Crypto.Hash import SHA256 f = open('progress.txt', 'r') password = ("abda") hash_obj = SHA256.new(password.encode('utf-8')) hkey = hash_obj.digest() def encrypt(info): msg = info BLOCK_SIZE = 16 PAD = "{" padding = lambda s: s

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BSides Jeddah CTF 2021: Category pcap / Writeup

Marco Schmidt/ Oktober 28, 2021/ IT-Security, Write-Ups/ 0Kommentare

BSides-Jeddah-CTF Writeups to the BSides Jeddah CTF – 2021 Situation – BSides Jeddah BSides Jeddah is coming up with a blueteam flavored CTF this year hosted by CyberDefenders. This will be a Jeopardy-style intermediate CTF with a few harder challenges, including network analysis, memory forensics, and malicious document analysis. To get latest updates, follow us on twitter @JeddahBsides , @CyberDefenders.

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BSides Jeddah CTF 2021: Category memdump / Writeup

Ulli Weichert/ Oktober 28, 2021/ IT-Security, Write-Ups/ 0Kommentare

BSides-Jeddah-CTF Writeup to the BSides Jeddah CTF – 2021 Situation – BSides Jeddah BSides Jeddah is coming up with a blueteam flavored CTF this year hosted by CyberDefenders. This will be a Jeopardy-style intermediate CTF with a few harder challenges, including network analysis, memory forensics and malicious document analysis. To get the latest updates, follow us on twitter @JeddahBsides ,

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DEADFACE CTF 2021: Steganography9 – Spectres / Writeup

Marco Schmidt/ Oktober 26, 2021/ IT-Security, Write-Ups/ 0Kommentare

Spectres Points 450 Description We intercepted this image from a suspected insider threat at De Monne Financial. It looks like parts of the image were cut out, but based on conversations between DEADFACE and the insider, we believe DEADFACE’s wallet address is hidden in this image. Image Getting the flag Take the picture to https://aperisolve.fr/ -> Just read the flag

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