Authenticated encryption protects data confidentiality and integrity in one cryptographic operation. It encrypts plaintext so unauthorized readers cannot understand it, and generates an authentication tag that lets the recipient detect altered or forged ciphertext. Common modes include AES-GCM and ChaCha20-Poly1305.
In cybersecurity, this helps prevent attackers from quietly changing encrypted files, messages, or stored records. Implementations must verify the authentication tag before using decrypted data, and must follow requirements such as never reusing a nonce with the same key. Authenticated encryption cannot compensate for exposed or hardcoded keys: if an attacker obtains the key, they may be able to decrypt data and create valid tags. Secure key generation, storage, and management remain essential.