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Comprehensive collection of CTF challenges, solutions, and insights.


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WHAMazon! JWT 3 - RSA Revenge

Using provided RSA private key components to manually implement PKCS#1 v1.5 signing and forge a valid RS256 JWT admin token.

WHAMazon! Crypto 5 - Signature Residue

Exploiting a weak (low) DSA nonce k to brute-force the signing secret, recover the private key x, and derive the flag via SHA-256.