CVE-2026-95666
MEDIUM
NVD
CVSS Score
4.3
Severity
MEDIUM
Published
Sep 22, 2026
Vendor
unknown
Description
Mattermost versions 11.9.x <= 11.9.1, 11.8.x <= 11.8.5, 11.7.x <= 11.7.10, 11.10.x <= 11.10.1 fail to limit the length of the post ID array accepted by the bulk reactions endpoint which allows an authenticated user to cause excessive database load via a crafted request to { {POST /api/v4/posts/ids/reactions} }.. Mattermost Advisory ID: MMSA-2026-00771