Fernet Cryptography

Fernet provides high-level, authenticated symmetric encryption for Python applications using AES-128 and HMAC-SHA256 to ensure data remains confidential and untampered.

Fernet is the standard implementation for symmetric encryption in the Python cryptography package. It handles the heavy lifting by combining AES-128 in CBC mode with PKCS7 padding and an HMAC-SHA256 signature. This design prevents common vulnerabilities like padding oracle attacks. Every token includes a 64-bit timestamp to block replay attempts and a 128-bit initialization vector for uniqueness. It is the go-to choice for securing session tokens or sensitive API keys where you need a proven, high-level implementation without manual cipher management.

https://cryptography.io/en/latest/fernet/