| id: GO-2026-4520 |
| modules: |
| - module: github.com/mattermost/mattermost-server |
| vulnerable_at: 11.4.1+incompatible |
| - module: github.com/mattermost/mattermost-server |
| versions: |
| - introduced: 10.11.0+incompatible |
| vulnerable_at: 11.4.1+incompatible |
| - module: github.com/mattermost/mattermost-server |
| versions: |
| - introduced: 11.1.0+incompatible |
| vulnerable_at: 11.4.1+incompatible |
| - module: github.com/mattermost/mattermost-server |
| versions: |
| - introduced: 11.2.0+incompatible |
| vulnerable_at: 11.4.1+incompatible |
| - module: github.com/mattermost/mattermost-server/v5 |
| non_go_versions: |
| - fixed: 5.3.2-0.20251212052346-61651b0df7ea |
| vulnerable_at: 5.39.3 |
| - module: github.com/mattermost/mattermost-server/v6 |
| vulnerable_at: 6.7.2 |
| - module: github.com/mattermost/mattermost/server/v8 |
| versions: |
| - fixed: 8.0.0-20251212052346-61651b0df7ea |
| summary: Mattermost fails to properly validate login method restrictions in github.com/mattermost/mattermost-server |
| cves: |
| - CVE-2026-0999 |
| ghsas: |
| - GHSA-3c9r-7f29-qp32 |
| references: |
| - advisory: https://github.com/advisories/GHSA-3c9r-7f29-qp32 |
| - advisory: https://nvd.nist.gov/vuln/detail/CVE-2026-0999 |
| - web: https://github.com/mattermost/mattermost/commit/61651b0df7ea5db55d1e54f8d6fb5fce4149309c |
| - web: https://mattermost.com/security-updates |
| notes: |
| - fix: 'module merge error: could not merge versions of module github.com/mattermost/mattermost-server: introduced and fixed versions must alternate' |
| - fix: 'github.com/mattermost/mattermost/server/v8: could not add vulnerable_at: could not find tagged version between introduced and fixed' |
| source: |
| id: GHSA-3c9r-7f29-qp32 |
| created: 2026-02-23T12:11:46.52600457-05:00 |
| review_status: UNREVIEWED |
