Meta Pauses Muse Sharing After More Than 6,800 Shared-Chat Hostnames Surface

Meta paused sharing in its Muse AI agent after Claroc researchers found more than 6,800 hostnames for shared chats, including pages with sensitive information that had been accessible without an account.

One search returned more than 6,800 share hostnames after scan noise was filtered out. Each hostname represented a share; the count does not represent affected users or sensitive conversations.

Muse placed a conversation title and a random identifier in each share hostname. A passive-DNS record could store the hostname after a lookup, and researchers could use it to reconstruct the share link. A review of a few hundred pages found mostly ordinary material. Sensitive examples included a small-business loan application, an internal revenue review, a to-do list containing a bank fraud alert and part of an account number, and a candidate’s preparation notes for a confidential executive-search call.

Meta introduced Muse on Sept. 8 as an AI agent that works through services users select, including email, calendars and financial accounts. Claroc submitted the issue to Meta’s bug bounty program on Oct. 8.

“However, we’ve paused this functionality while we review this report and consider changes to how these links can be discovered,” Meta said. On Oct. 20, researchers rechecked 40 shares they had previously opened. None opened in that check, and the hostnames returned errors, while the titles remained in historical DNS records.