Mattermost server Vulnerabilities

Security vulnerability tracking for Mattermost Mattermost server

Last updated: Feb 16, 2026
Total CVEs

6

Critical

0

With Exploits

5

Last 30 Days

0

Vulnerability Timeline

6 vulnerabilities discovered over time for Mattermost server

Severity Distribution

Critical0
0%
High0
0%
Medium6
100%
Low1
17%
DescriptionVendor / ProductExploit Status
CVE-2025-143504.3

This vulnerability allows an attacker who is already logged into Mattermost to find out the names and URLs of teams they shouldn't have access to by posting links in channels and checking the system's responses. It affects specific versions of Mattermost and highlights a failure to properly check if a user is part of a team before revealing its information.

mattermostmattermost server
Exploit Available
about 2 months agoFeb 16, 2026
CVE-2025-138215.7

This vulnerability allows an attacker to steal sensitive information, like password hashes and multi-factor authentication secrets, from other users by manipulating their profile nickname or during email verification events. The attacker must already be logged in as an authenticated user on the affected versions of Mattermost to exploit this weakness.

mattermostmattermost server
Exploit Available
about 2 months agoFeb 16, 2026
CVE-2026-09994.3

This vulnerability allows an attacker who is already logged in to bypass single sign-on (SSO) requirements and use a userID-based login instead. It affects specific versions of Mattermost, meaning only users on those versions are at risk.

mattermostmattermost server
Exploit Available
about 2 months agoFeb 16, 2026
CVE-2026-09984.3

This vulnerability allows an attacker to start Zoom meetings as any user and change posts in Mattermost by tricking the system into thinking they are someone else. It affects specific versions of Mattermost and requires the attacker to have access to the API, meaning they need to be able to send requests to the server.

mattermostmattermost server
Exploit Available
about 2 months agoFeb 16, 2026
CVE-2026-09974.3

This vulnerability allows any logged-in user to change Zoom meeting settings for any channel in Mattermost by sending specially crafted requests. It affects specific versions of Mattermost and the Zoom plugin, meaning that if you're using those versions, an attacker could exploit this flaw without needing special access.

mattermostmattermost server
Theoretical
about 2 months agoFeb 16, 2026
CVE-2026-228924.3

An attacker who has access to the Jira plugin in Mattermost can exploit a flaw to read messages and attachments from private channels they shouldn't have access to by using the ID of a specific post. This vulnerability affects certain versions of Mattermost and requires the attacker to be authenticated in the system.

mattermostmattermost server
Theoretical
about 2 months agoFeb 13, 2026

About Mattermost Mattermost server Security

This page provides comprehensive security vulnerability tracking for Mattermost Mattermost server. Our database includes all CVEs affecting this product, updated in real-time from official sources.

Each vulnerability listing includes detailed CVSS severity analysis, exploit availability status, AI-generated explanations, and direct links to official security patches and vendor advisories.

Security Recommendations

  • • Always keep Mattermost server updated to the latest version
  • • Subscribe to security advisories from Mattermost
  • • Monitor this page for new vulnerabilities affecting your version
  • • Prioritize patching critical and high severity issues immediately