What is CVE-2026-93847?

CVE-2026-93847 is a low-severity vulnerability in Mattermost, classified under Incorrect Authorization. CVSS score: 3.5/10. Published 2026-10-26.

How severe is CVE-2026-93847?

Low severity. CVSS v3 base score is 3.5 out of 10.

Auth bypass in Mattermost

CVE-2026-93847

Mattermost versions 11.7.x <= 11.7.10 fail to validate reserved system post types on the scheduled post creation and publication paths which allows an authenticated channel member to publish messages rendering as trusted system events via the scheduled post endpoint.. Mattermost Advisory ID: MMSA-2026-00732

Vulnerability class: Broken Access Control

Published 2026-10-26 · last modified 2026-10-26.

CVSS v3 metric

CVSS v3 base score 3.5 (Low). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Mattermost

Weakness classification (CWE)

CWE-863 — Incorrect Authorization

References

mattermost.com/security-updates (vendor-advisory)

Frequently asked questions

What is CVE-2026-93847?: CVE-2026-93847 is a low-severity vulnerability in Mattermost, classified under Incorrect Authorization. CVSS score: 3.5/10. Published 2026-10-26.
How severe is CVE-2026-93847?: Low severity. CVSS v3 base score is 3.5 out of 10.