What is CVE-2026-2461?

CVE-2026-2461 is a medium-severity vulnerability in Mattermost, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 4.3/10. Published 2026-03-16.

How severe is CVE-2026-2461?

Medium severity. CVSS v3 base score is 4.3 out of 10.

Auth bypass in Mattermost

CVE-2026-2461

Mattermost Plugins versions <=11.3 11.0.3 11.2.2 10.10.11.0 fail to implement authorisation checks on comment block modifications, which allows an authorised attacker with editor permission to modify comments created by other board members…

Vulnerability class: IDOR (Insecure Direct Object Reference)

EPSS: 0.000 (12.9th percentile) — read the EPSS interpretation.

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:N/I:L/A:N.

Affected products

Mattermost — versions 0, 11.4.0, 11.3.1

Weakness classification (CWE)

CWE-639 — Authorization Bypass Through User-Controlled Key

References

MMSA-2025-00559 (vendor-advisory)

Frequently asked questions

What is CVE-2026-2461?: CVE-2026-2461 is a medium-severity vulnerability in Mattermost, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 4.3/10. Published 2026-03-16.
How severe is CVE-2026-2461?: Medium severity. CVSS v3 base score is 4.3 out of 10.