VDB
CVE-2026-20796
CVE-2026-20796
PUBLISHED
CVSS 3.0999999046325684 LOW
Mattermost versions 11.1.x <= 11.1.2, 10.11.x <= 10.11.9, 11.2.x <= 11.2.1 fail to sanitize sensitive data in WebSocket messages which allows authenticated users to exfiltrate password hashes and MFA secrets via profile nickname updates or email verification events. Mattermost Advisory ID: MMSA-2025-00560
EPSS 0.01% · 1.4th percentile
Risk Scores
CVSS 3.1
3.0999999046325684
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N
EPSS Score
0.01%
1.4th percentile
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| mattermost | mattermost_server | 10.11.0 |
| Mattermost | Mattermost | 10.11.0, 10.11.10, 11.3.0 |
| github.com | mattermost/mattermost-server | 10.11.0 |
Timeline
- Jan 16, 2026 CVE Published
- Feb 13, 2026 EPSS Score
- Feb 14, 2026 PoC Published
- Feb 15, 2026 EPSS Score
- Feb 17, 2026 EPSS Score
- Feb 19, 2026 EPSS Score
- Feb 21, 2026 EPSS Score
- Feb 23, 2026 EPSS Score
- Feb 25, 2026 EPSS Score
- Feb 27, 2026 EPSS Score
- Feb 28, 2026 EPSS Score
- Mar 2, 2026 EPSS Score
References
- https://mattermost.com/security-updates/ advisory
- MMSA-2025-00549 vendor-advisory
- https://nvd.nist.gov/vuln/detail/CVE-2026-20796 advisory
- https://github.com/mattermost/mattermost package