Topology

Hack The Box. Linux. Easy machine

5 minutes to read

This machine contains a website that allows to generate equations using LaTeX. With this feature we can read arbitrary files from the server with LaTeX injection techniques and find a hashed password for another subdomain, which can be cracked. This password is reused in SSH. After that, root is executing gnuplot scripts periodically, which leads to the privilege escalation

Big RSA

TeamItaly CTF 2023

4 minutes to read

RSA. Factorial. Modular arithmetic. Integer division

Scrambled Pizzeria

TeamItaly CTF 2023

6 minutes to read

XOR. Permutations and substitutions

Lucky Number

Hack.lu CTF 2023

5 minutes to read

Mersenne primes. Sum of divisors

Spooky Safebox

Hack.lu CTF 2023

9 minutes to read

ECC. ECDSA. Public key recovery. Biased nonces. Hidden Number Problem. LLL lattice reduction

Prime

Balsn CTF 2023

9 minutes to read

AKS primality test. Carmichael numbers. Euler totient function

Web3

Balsn CTF 2023

3 minutes to read

Web3. Ethereum addresses and signatures

qcg-k

corCTF 2023

5 minutes to read

DSA. Recurrence relation. Nonces