CVE-2026-4265
Published: Mar 16, 2026
Modified: Mar 16, 2026
CVSS v3.1
4.3
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
| Vendor | Product | Versions |
|---|---|---|
Mattermost | Mattermost | affected 11.3.0 - <= 11.3.0affected 11.2.0 - <= 11.2.2affected 10.11.0 - <= 10.11.10unaffected 11.4.0unaffected 11.3.1+2 more versions |
Weaknesses (CWE)
CVSS v3.1 Details
CVSS v3.1 Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability
References
Security Training
Train your team to recognize and prevent security threats with our comprehensive security awareness program.
Start TrainingVulnerability Scanning
Discover vulnerabilities in your applications and infrastructure before attackers do.
Scan Now