What is CVE-2026-2462?

CVE-2026-2462 is a medium-severity vulnerability in Mattermost, classified under Incorrect Authorization. CVSS score: 6.6/10. Published 2026-03-16.

How severe is CVE-2026-2462?

Medium severity. CVSS v3 base score is 6.6 out of 10.

Auth bypass in Mattermost

CVE-2026-2462

Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to restrict plugin installation on CI test instances with default admin credentials which allows an unauthenticated attacker to achieve remote code execution and exfiltrate sensitive configuration data including AWS and SMTP credentials via uploading a malicious plugin after changing the import directory. Mattermost Advisory ID: MMSA-2025-00528

Vulnerability class: Broken Access Control

EPSS: 0.003 (25.3th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.6 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:L/I:L/A:L.

Affected products

Mattermost — versions 11.3.0, 11.2.0, 10.11.0
Mattermost Mattermost_server

Weakness classification (CWE)

CWE-863 — Incorrect Authorization

References

responsibledisclosure@mattermost.com (vendor-advisory, Vendor Advisory)

Frequently asked questions

What is CVE-2026-2462?: CVE-2026-2462 is a medium-severity vulnerability in Mattermost, classified under Incorrect Authorization. CVSS score: 6.6/10. Published 2026-03-16.
How severe is CVE-2026-2462?: Medium severity. CVSS v3 base score is 6.6 out of 10.