Go/github.com/mattermost/mattermost-server CVE-2026-4915: medium 6.5, EPSS 0.28%
Mattermost doesn't filter nil elements from outgoing webhook attachment payloads before processing in github.com/mattermost/mattermost-server
Action: Upgrade github.com/mattermost/mattermost-server to 10.11.15+incompatible or later.
go get github.com/mattermost/mattermost-server@v10.11.15+incompatiblego get github.com/mattermost/mattermost-server@v11.4.5+incompatiblego get github.com/mattermost/mattermost-server@v11.5.4+incompatiblego get github.com/mattermost/mattermost-server@v11.6.1+incompatibleAffected
| introduced | fixed | last affected |
|---|---|---|
| 10.11.0+incompatible | 10.11.15+incompatible | - |
| 11.4.0+incompatible | 11.4.5+incompatible | - |
| 11.5.0+incompatible | 11.5.4+incompatible | - |
| 11.6.0+incompatible | 11.6.1+incompatible | - |
Fixed versions
| 10.11.15+incompatible | 11.4.5+incompatible | 11.5.4+incompatible | 11.6.1+incompatible |
Sources
- osv: GO-2026-5845
- nvd: CVE-2026-4915
- https://github.com/advisories/GHSA-5gmf-x7hg-97wf
- https://github.com/mattermost/mattermost/commit/faa7d75b4ea041701e97948f8aa1332e3626a39a
- https://mattermost.com/security-updates
CVE-2026-4915 · published · modified · JSON