# Insomni'hack teaser 2023 - GCM

*This is the solution of the challenge “GCM” given during the Insomni’hack teaser 2023. It was an example of nonce re-use in AES GCM computation.*

*This is the solution of the challenge “GCM” given during the Insomni’hack teaser 2023. It was an example of nonce re-use in AES GCM computation.*

*This is the solution of the challenge “0KPR00F” given during the Real World CTF 2023. It consists in building a proof of knowledge of a polynomial with precomputed values to solve the challenge.*

*This is the solution of the challenge “Counting On You” given during the GreHack 2022 CTF. It consisted in a nonce reuse attack on AES CTR using a weak PRNG for nonce.*

*This is the solution of the challenge “Custom GCM” given during the Black Alps 2022 CTF. It was an implementation error of the nonce usage in AES GCM computation lead to forgery attack.*

*This is the solution of the challenge “Mariana” given during the ASIS CTF 2022. It consisted in solving 40 discrete logarithm fixed points to solve the challenge. The range check allows to solve the equation with the Chinese remainder theorem with a negative value.*

*This is the solution of the challenge “Squaring Off” given during the MCH CTF. It consisted in solving the elliptic curve discrete logarithm with unknown curve parameters and unknown y coordinate.*