CVE-2026-95666
MEDIUMCVSS 4.3Description
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
Timeline
Published:September 22nd, 2026 2:17 PM
Last modified:October 7th, 2026 4:48 PM
CVSS Scoring
CVSS v3: 4.3 (MEDIUM)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
Affected Software
From NVD CPE configuration data
Vendors
mattermost
Products
mattermost_server
Weaknesses (CWE)
References & Reports
Advisories, patches, and third-party reports
Source: NIST NVD · Data may lag official sources by up to one minute