GHSA-5mr9-crcg-8wh2
Mattermost fails to use consistent error responses when handling the /mute command
Packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| Go | github.com/mattermost/mattermost/server/v8 | < 8.0.0-20260130144323-5bb5261c72fa | 8.0.0-20260130144323-5bb5261c72fa |
| Go | github.com/mattermost/mattermost-server | < 5.3.2-0.20260130144323-5bb5261c72fa | 5.3.2-0.20260130144323-5bb5261c72fa |
| Go | github.com/mattermost/mattermost-server | >= 10.11.0-rc1, < 10.11.11 | 10.11.11 |
| Go | github.com/mattermost/mattermost-server | >= 11.2.0-rc1, < 11.2.3 | 11.2.3 |
| Go | github.com/mattermost/mattermost-server | >= 11.3.0-rc1, < 11.3.1 | 11.3.1 |
Details
As written in the advisory (Markdown source, shown as plain text).
Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to use consistent error responses when handling the /mute command which allows an authenticated team member to enumerate private channels they are not authorized to know about via differing error messages for nonexistent versus private channels. Mattermost Advisory ID: MMSA-2026-00588
References
External links from the advisory. They lead to third-party sites.