Description
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
CVSS breakdown
CVSS 3.1
Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
None
Availability
None
Affected products
- Mattermost / Mattermost11.7.0 – 11.7.0
- Mattermost / Mattermost11.6.0 – 11.6.2
- Mattermost / Mattermost11.5.0 – 11.5.5
- Mattermost / Mattermost10.11.0 – 10.11.17
- Mattermost / Mattermost11.8.0 – 11.8.0
- Mattermost / Mattermost11.7.1 – 11.7.1
- Mattermost / Mattermost11.6.3 – 11.6.3
- Mattermost / Mattermost11.5.6 – 11.5.6
- Mattermost / Mattermost10.11.18 – 10.11.18