AES - GCM Mode

AES Galois Counter Mode is an authenticated encryption mode. For each encryption it produces a tag that can be used to verify the integrity of the message. It is considered secure and is used in TLS.

Definition

Attacks

• Forbidden attack - CryptoHack

  When the nonce (IV) is reused in 2 different messages, an attacker can forge a tag for any ciphertext.

  Cryptopals - Detailed explanation of the attack.

  GitHub - Implementation of the attack.

  GitHub (Crypton) - Summary of the attack.

  This custom python script gives an example implementation of the attack.

  • forbidden_attack.py