CVEvulnerability
CVE-2026-4265
4.3 MEDIUM
Official page ↗
- Status
- Analyzed
- Published
- 2026-03-16
- Last modified
- 2026-06-17
- Assigner
- [email protected]
- CVSS 3.1 ([email protected])
- 4.3 MEDIUM — CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
- Weaknesses
- CWE-863
Description
Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to validate team-specific upload_file permissions which allows a guest user to post files in channels where they lack upload_file permission via uploading files in a team where they have permission and reusing the file metadata in a POST request to a different team. Mattermost Advisory ID: MMSA-2025-00553
Affected configurations
• mattermost mattermost server (>= 10.11.0 < 10.11.11)
• mattermost mattermost server (>= 11.2.0 < 11.2.3)
• mattermost mattermost server (>= 11.3.0 < 11.3.1)
Related
Weakness · CWE (1)
- CWE-863 Incorrect Authorization weakness
References
- https://mattermost.com/security-updates Vendor Advisory