PFS
Abbreviation · Security & Infosec
Definitions
Short for perfect forward secrecy, a property in which compromise of a long-term private key does not let an attacker decrypt previously captured sessions because each session used ephemeral key agreement. PFS is a major reason modern TLS configurations prefer ephemeral Diffie-Hellman-based handshakes.
In plain English: A security property that keeps old encrypted sessions safe even if a long-term key is later stolen.
Example: "The TLS configuration review required PFS so stolen server keys would not expose months of recorded traffic."