Go/github.com/mattermost/mattermost-server CVE-2026-21386: medium 4.3, EPSS 0.19%
Mattermost fails to use consistent error responses when handling the /mute command
Action: Upgrade github.com/mattermost/mattermost-server to 5.3.2-0.20260130144323-5bb5261c72fa or later.
go get github.com/mattermost/mattermost-server@v5.3.2-0.20260130144323-5bb5261c72fago get github.com/mattermost/mattermost-server@v10.11.11go get github.com/mattermost/mattermost-server@v11.2.3go get github.com/mattermost/mattermost-server@v11.3.1Affected
| introduced | fixed | last affected |
|---|---|---|
| 0 | 5.3.2-0.20260130144323-5bb5261c72fa | - |
| 10.11.0-rc1 | 10.11.11 | - |
| 11.2.0-rc1 | 11.2.3 | - |
| 11.3.0-rc1 | 11.3.1 | - |
Fixed versions
| 5.3.2-0.20260130144323-5bb5261c72fa | 10.11.11 | 11.2.3 | 11.3.1 |
Sources
- osv: GHSA-5mr9-crcg-8wh2#Go/github.com/mattermost/mattermost-server
- https://nvd.nist.gov/vuln/detail/CVE-2026-21386
- https://github.com/mattermost/mattermost/commit/5bb5261c72faa476558a694c23581d24b734da41
- https://github.com/mattermost/mattermost
- https://mattermost.com/security-updates
CVE-2026-21386 · published · modified · JSON