crypto
mayday-mayday
Advanced RSA attack exploiting MSB leaks from CRT exponents. Uses the Coppersmith method and lattice-based reduction to factor large moduli.
by r98inver
3 min
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crypto 6 writeups
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keysharer
High-level Cryptography solve demonstrating the Invalid Curve Attack. Explains how to recover a secret key by sending points from curves with lower orders.
by r98inver
5 min
crypto
Substitution Ciphers
Classic cryptography overview featuring Caesar and Vigenere Ciphers. Demonstrates single-byte XOR bruteforcing and frequency analysis for multi-key XOR decryption.
by r98inver
7 min
crypto
RSA Challenges
Comprehensive walkthrough of three RSA challenges from CTF101, covering basic decryption, factoring using online tools, and exploiting totient multiples from leaked private exponents.
by r98inver
5 min
crypto
Encoding Challenges
Step-by-step guide to reversing complex data encodings. Covers nested Base64/Base16 loops and a custom bit-shifting 'magic shuffle' algorithm.
by r98inver
3 min
crypto
apbq-rsa-1
RSA factoring challenge using specific linear combination hints. Employs a brute-force GCD attack on coprime hint coefficients to recover the private key.
by r98inver
4 min