CVE-2025-0503 Leaked User IDs and Metadata of Deleted DMs

Mattermost versions 9.11.x = 9.11.6 fail to filter out DMs from the deleted channels endpoint which allows an attacker to infer user IDs and other metadata from deleted DMs if someone had manually marked DMs as deleted in the database...

CVE-2025-0503

Mattermost 9.11.x

PT-2025-6788 · Mattermost · Mattermost

Name of the Vulnerable Software and Affected Versions: Mattermost versions 9.11.x through 9.11.6 Description: The issue allows an attacker to infer user IDs and other metadata from deleted direct messages DMs if someone had manually marked DMs as deleted in the database. This is possible because...