Medium severity4.3NVD Advisory· Published Jun 22, 2026· Updated Jun 23, 2026
CVE-2026-9162
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
AI Insight
LLM-synthesized narrative grounded in this CVE's description and references.
Affected packages
Versions sourced from the GitHub Security Advisory.
| Package | Affected versions | Patched versions |
|---|---|---|
github.com/mattermost/mattermost-serverGo | >= 11.7.0, < 11.7.1 | 11.7.1 |
github.com/mattermost/mattermost-serverGo | >= 11.6.0, < 11.6.3 | 11.6.3 |
github.com/mattermost/mattermost-serverGo | >= 11.5.0, < 11.5.6 | 11.5.6 |
github.com/mattermost/mattermost-serverGo | >= 10.11.0, < 10.11.18 | 10.11.18 |
Affected products
2<=11.7.0, <=11.6.2, <=11.5.5, <=10.11.17+ 1 more
- (no CPE)range: <=11.7.0, <=11.6.2, <=11.5.5, <=10.11.17
- cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*range: >=10.11.0,<10.11.18
Patches
Vulnerability mechanics
References
3- github.com/advisories/GHSA-h998-hxxj-8q83ghsaADVISORY
- mattermost.com/security-updatesnvdVendor AdvisoryWEB
- nvd.nist.gov/vuln/detail/CVE-2026-9162ghsaADVISORY
News mentions
1- Mattermost: Six Vulnerabilities in User Management, Plugins, and Sessions Disclosed TogetherVypr Intelligence · Jun 22, 2026