2026weight 24.14Insomni'hack Team

Insomni'hack 2026

2 challenges with 6 published community solutions between them. Solution links go to CTFtime’s task page, which aggregates every writeup for a challenge - individual blog posts rot, the aggregator does not.

Full task list on CTFtime

Cryptography1

Recover a plaintext or a key from something that was supposed to protect it. In practice: identify the scheme, find the parameter the author got wrong, exploit it.

Solve it with:Cipher identifier and automatic decoder Vigenere cipher solver with automatic key recovery RSA decryption and attack runner Wiener’s attack on small RSA private exponents In-browser hash cracker with rule transforms Learn: Classical ciphers and frequency analysis Learn: RSA and the parameters that break it

smooth-RSA
1 pts1 writeup
Also written up in: kyos-public/ctf-writeups, kyos-public/ctf-writeups
Same technique in picoCTF: It's Not My Fault 2, StegoRSA, john_pollard

Misc1

Everything that fits no other box: esolangs, puzzles, scripting exercises, and the jail escapes that have not yet earned their own category.

Solve it with:Brainfuck and esolang decoder Cipher identifier and automatic decoder Regex tester with match offsets and capture groups Learn: Recognising encodings

Escape
1 pts1 writeup
Also written up in: semchapeu/CTF-WriteUps, semchapeu/CTF-WriteUps
Same technique in picoCTF: PW Crack 2, Permissions, Specialer

Cryptography1

smooth-RSA

Misc1

Escape

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