Auth bypass in Mattermost
CVE-2025-41443
Mattermost versions 10.5.x <= 10.5.12, 10.11.x <= 10.11.2 fail to properly validate guest user permissions when accessing channel information which allows guest users to discover active public channels and their metadata via the `/api/v4/teams/{team_id}/channels/ids` endpoint
Vulnerability class: Broken Access Control
Published · last modified .
CVSS v3 metric
CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N.
EPSS exploit prediction
EPSS: 0.003 (21.0th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 21st percentile — 21.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: +0.000
Affected products
- Mattermost — versions 10.5.0, 10.11.0, 10.12.0
- Mattermost Server
Weakness classification (CWE)
References
- mattermost.com/security-updates (Vendor Advisory)
Frequently asked questions
- What is CVE-2025-41443?
- CVE-2025-41443 is a medium-severity vulnerability in Mattermost, classified under Missing Authorization. CVSS score: 4.3/10. Published 2025-10-16.
- How severe is CVE-2025-41443?
- Medium severity. CVSS v3 base score is 4.3 out of 10.