CVE-2026-6342
MEDIUM
NVD
CVSS Score
4.3
Severity
MEDIUM
Published
May 18, 2026
Vendor
unknown
Description
Mattermost Plugins versions <=11.5 11.1.5 10.13.11 11.3.4.0 fail to appropriately check for valid namespaces which allows plugin users to create subscriptions to groups that were not whitelisted via creating groups that share the same prefix as a whitelisted group. Mattermost Advisory ID: MMSA-2026-00601