VDB
CVE-2026-27659
CVE-2026-27659
PUBLISHED
CVSS 4.599999904632568 MEDIUM
Mattermost doesn't properly validate CSRF tokens
EPSS 0.03% · 9.4th percentile
Risk Scores
CVSS 3.1
4.599999904632568
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N
EPSS Score
0.03%
9.4th percentile
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| github.com | mattermost/mattermost/server/v8 | 11.4.0-rc1, 8.0.0-20260105080200, 10.11.0-rc1 |
| Mattermost | Mattermost | 11.4.1, 11.2.4, 10.11.12 |
| mattermost | mattermost_server | 11.2.0, 11.4.0, 10.11.0 |
Exploit Intelligence
- CIRCL seen: CVE-2026-20719 (circl-sighting)
- CIRCL seen: CVE-2026-27659 (circl-sighting)
- CIRCL seen: CVE-2026-27659 (circl-sighting)
- MMSA-2026-00578 (circl)
Timeline
- Feb 24, 2026 CVE Published
- Mar 25, 2026 Coalition ESS Score
- Mar 25, 2026 CVE Updated
- Mar 25, 2026 PoC Published
- Mar 25, 2026 PoC Published
- Mar 26, 2026 PoC Published
- Mar 26, 2026 Security Advisory
- Mar 29, 2026 Security Advisory
- May 18, 2026 EPSS Score
- May 19, 2026 EPSS Score
- May 20, 2026 EPSS Score
- May 21, 2026 EPSS Score
References
- https://mattermost.com/security-updates/ advisory
- MMSA-2026-00578 vendor-advisory
- https://nvd.nist.gov/vuln/detail/CVE-2026-27659 advisory
- https://github.com/mattermost/mattermost package