CVE-2026-9162 — Global session revocation does not invalidate active WebSocket connections
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 dur…
Published: 2026-06-22 · CVSS: 4.3 · CVSS 3.1
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
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7