CVE-2026-86348

Mattermost versions <=11.9 11.0.9 11.4.8 11.7.7 10.22.11.0 fail to recover from handler panics, which allows an authenticated user to crash the plugin via a post-action request with an unexpected field type.. Mattermost Advisory ID: MMSA-2026-00701

Score

CVSS 3.1 4.3 Medium

Status

Analyzed - responsibledisclosure@mattermost.com

Published

2026-09-14

Last modified

2026-10-14

Weaknesses

CWE-704

Affected products

• Mattermost (Mattermost)
• Mattermost Server (Mattermost)

References

• https://mattermost.com/security-updates