low3.1
CVE-2025-11777
Mattermost Incorrect Authorization vulnerability
Impact
Mattermost versions 10.11.x <= 10.11.3, 10.5.x <= 10.5.11 fail to properly validate team membership permissions in the Add Channel Member API, which allows users from one team to access user metadata and channel membership information from other teams via the API endpoint.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| go | github.com/mattermost/mattermost-server | >= 10.11.0, < 10.11.4 | 10.11.4 |
| go | github.com/mattermost/mattermost/server/v8 | < 8.0.0-20250905150616-ba86dfc5876b | 8.0.0-20250905150616-ba86dfc5876b |
| go | github.com/mattermost/mattermost | < 5.3.2-0.20250905150616-ba86dfc5876b | 5.3.2-0.20250905150616-ba86dfc5876b |
| go | github.com/mattermost/mattermost-server/v5 | < 5.3.2-0.20250905150616-ba86dfc5876b | 5.3.2-0.20250905150616-ba86dfc5876b |
| go | github.com/mattermost/mattermost-server/v6 | < 5.3.2-0.20250905150616-ba86dfc5876b | 5.3.2-0.20250905150616-ba86dfc5876b |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Mattermost | Mattermost Server | from 10.5.0 before 10.5.12 from 10.11.0 before 10.11.4 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://mattermost.com/security-updates
- https://github.com/advisories/GHSA-mqcj-8c2g-h97q
- https://nvd.nist.gov/vuln/detail/CVE-2025-11777
- https://github.com/mattermost/mattermost/commit/98acefe911dd9de7edf47a7d825dd99f53141a52
- https://github.com/mattermost/mattermost/commit/ba86dfc5876b354b9d3c20ff45c08ca6f8426149
- https://github.com/mattermost/mattermost/commit/d72d437f1567ba0b639b6e4fd73bab06c51baab5