GHSA-rmvv-8v8w-rf7x
Mattermost doesn't validate user-supplied input in API request handlers
Packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| Go | github.com/mattermost/mattermost-server | >= 11.6.0, < 11.6.1 | 11.6.1 |
| Go | github.com/mattermost/mattermost-server | >= 11.5.0, < 11.5.4 | 11.5.4 |
| Go | github.com/mattermost/mattermost-server | >= 11.4.0, < 11.4.5 | 11.4.5 |
| Go | github.com/mattermost/mattermost-server | >= 10.11.0, < 10.11.15 | 10.11.15 |
| Go | github.com/mattermost/mattermost-plugin-github | < 1.0.1-0.20260330164815-c2840e980b3c | 1.0.1-0.20260330164815-c2840e980b3c |
Details
As written in the advisory (Markdown source, shown as plain text).
Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to validate user-supplied input in API request handlers which allows an authenticated attacker to crash the plugin process via a crafted HTTP request to the PR details endpoint. Mattermost Advisory ID: MMSA-2026-00638
References
External links from the advisory. They lead to third-party sites.