Break Caesar and Vigenere ciphers using frequency analysis and known-plaintext attacks.
Analyze leaked password hashes, compare hash algorithms, and understand rainbow table attacks vs salted hashes.
Identify weak cipher suites, expired certificates, protocol downgrades, and BEAST/POODLE vulnerabilities.
Analyze RSA keys for small key sizes, shared prime factors, Wiener's attack indicators, and padding oracle vulnerabilities.
Analyze AES-ECB pattern weaknesses and perform known-plaintext attacks on a poorly implemented symmetric encryption system.
Exploit DSA nonce reuse and ECDSA k-value weakness to forge digital signatures and recover private keys.
Audit TLS certificate chains for validation flaws including self-signed intermediates, expired CAs, and certificate transparency issues.
Audit a breached password database for insecure hashing practices including plaintext, MD5, SHA1, and unsalted storage.
Audit database and file system encryption to identify unprotected data stores and key management vulnerabilities.
Analyze Diffie-Hellman key exchange vulnerabilities including small subgroup attacks, Logjam, and static vs ephemeral key dangers.
Review format-preserving encryption (FPE) and tokenization implementations for boundary violations and cryptographic weaknesses.
Assess organizational cryptographic inventory for quantum vulnerability and plan migration to post-quantum algorithms.