Vulnerability Details CVE-2026-9162
Mattermost versions 11.7.x <= 11.7.0, 11.6.x <= 11.6.2, 11.5.x <= 11.5.5, 10.11.x <= 10.11.17 fail to invalidate cached authentication state for active WebSocket connections during global session revocation, which allows a user with an existing WebSocket connection to remain authenticated and continue receiving real-time events until the cached session expires or the client reconnects.. Mattermost Advisory ID: MMSA-2026-00664
Exploit prediction scoring system (EPSS) score
EPSS Score 0.002
EPSS Ranking 10.0%
CVSS Severity
CVSS v3 Score 4.3
References