Headline
GHSA-9hh7-6558-qfp2: Mattermost allows other users to determine when users had read channels via channel member objects
Mattermost versions 10.11.x <= 10.11.3, 10.5.x <= 10.5.11 fail to enforce access permissions on the Agents plugin which allows other users to determine when users had read channels via channel member objects.
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- GitHub Advisory Database
- GitHub Reviewed
- CVE-2025-55074
Mattermost allows other users to determine when users had read channels via channel member objects
Low severity GitHub Reviewed Published Nov 18, 2025 to the GitHub Advisory Database • Updated Nov 18, 2025
Package
gomod github.com/mattermost/mattermost-server (Go)
Affected versions
>= 10.11.0, < 10.11.4
>= 10.5.0, < 10.5.12
Patched versions
10.11.4
10.5.12
gomod github.com/mattermost/mattermost/server/v8 (Go)
< 8.0.0-20250905150616-ba86dfc5876b6
8.0.0-20250905150616-ba86dfc5876b6
Description
Published to the GitHub Advisory Database
Nov 18, 2025
Last updated
Nov 18, 2025
EPSS score