GHSA-h998-hxxj-8q83MediumCVSS 4.3

Mattermost doesn't invalidate cached authentication state for active WebSocket connections during global session revocation

Published
June 22, 2026
Last Modified
September 15, 2026

🔗 CVE IDs covered (1)

CVE-2026-9162 →

📋 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

🎯 Affected products4

  • go/github.com/mattermost/mattermost-server:>= 11.7.0, < 11.7.1
  • go/github.com/mattermost/mattermost-server:>= 11.6.0, < 11.6.3
  • go/github.com/mattermost/mattermost-server:>= 11.5.0, < 11.5.6
  • go/github.com/mattermost/mattermost-server:>= 10.11.0, < 10.11.18

🔗 References (3)