Facebook Unveils New Encryption Protocol for Group Chats

Researchers at Facebook have published a new encryption protocol for group chats called Asynchronous Ratcheting Tree (ART) on GitHub. The ART protocol enables secure group messaging, even if one of the participants has been fully compromised.

Addressing Security Issues in Group Chats

According to the researchers, ART solves security problems present in popular applications such as WhatsApp, Facebook Messenger, and Signal. While these apps offer strong encryption for one-on-one conversations, their group chat encryption features have notable weaknesses. If an attacker compromises one group member, they can intercept messages for an unlimited period of time.

How the ART Protocol Works

The protocol uses an asymmetric prekeys model, allowing users to obtain secure group keys. Additionally, ART employs a one-time asymmetric setup key, which enables the group administrator to generate private keys for all chat participants when the group is created.

Experts note that ART allows for secure group messaging even if one participant is completely compromised, significantly improving the security of group chats.

Context and Industry Impact

ART was published just one day after FBI Director Christopher Wray spoke about the challenges the agency faces due to encryption on mobile devices.