CTF Writeups
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shellCTF – Encoder (Cryptography)
Another challenge in the shellCTF Cryptography category was called encoder and this is how it was solved. Using Cybershef I chose the Encryption / Encoding category and moved the ROT13 block to the Recipe. ROT13 which is a simple Caeser cipher. Using this cipher I chose the rotate amount to 19 to get the flag. (-7 will also work as 26 – 7 is 19). Below is a short video to show the process:
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shellCTF – Algoric Shift (Cryptography)
Tiens (Verniel) competed in the shellCTF this past weekend and here’s the first solution to the flag for the first Cryptography challenge. The challenge was called “Algoric-Shift” and we were given the below: Download the script.py to decrypt the above ciphered text. To view the code please watch the video below for this challenge as I do not want to share it since it is not my code. In short there is a text variable containing a string ‘flag{…}’, the program contains 3 lists and checks the length of the text variable. It then does a modulus on each and appends each character to a list. I pasted the ciphered…
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Jeresy CTF
Tiens (Verniel) competed in the Jersey CTF in April with 3 amazing people he met in the Discord server for the CTF. This was his first CTF and the team name used were Bytesize. The challenges were a lot of fun and some quite challenging. The event had various speakers during the CTF that was very interesting and informative. The staff was very helpful and resourceful if you got stuck with a particular challenge. The team eventually placed in the top 10 over all and a lot was learnt and even more fun was had. Great new friendships were also made. The video below from CryptoCat runs through the challenges.…