Types of Cryptographic Attacks

Cryptography · Axiom Academy

LESSON Types of Cryptographic Attacks Understanding the different attack models and what information adversaries possess What the attacker knows: Only the encrypted messages (ciphertext). In a ciphertext-only attack, the adversary intercepts encrypted communications but has no knowledge of the original plaintext. This is the weakest attack model from the attacker's perspective, yet many historical ciphers have been broken under these conditions. What the attacker knows: Some plaintext-ciphertext pairs. In a known-plaintext attack, the adversary has access to both some encrypted messages and their corresponding original plaintext. This additional information can help reveal patterns in the encryption scheme or recover the encryption key. What the attacker knows: Ciphertexts for plaintexts of their choosing. In a chosen-plaintext attack (CPA), the adversary can choose arbitrary messages and obtain their encryptions. This is a powerful attack model that simulates scenarios where an attacker can influence what gets encrypted. What the attacker knows: Plaintexts for ciphertexts of their choosing (plus all information from CPA). In a chosen-ciphertext attack (CCA), the adversary can choose arbitrary ciphertexts and obtain their decryptions. This is the strongest attack model and represents scenarios where an attacker has temporary access to a decryption oracle.

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