Dashboard / CVE-2026-93851

CVE-2026-93851

HIGH
MEDIUM Priority: 0.02 BB Relevance: 46/100
Published: 2026-10-28 Modified: 2026-10-29 First seen: 2026-10-29 Status: active

Attack Surface

Network Conf. Impact Integ. Impact Scope Change

CVSS Vector Breakdown

AV: Network
AC: High
PR: Low
UI: Required
S: Changed
C: High
I: High
A: High

Description

Mattermost versions 11.9.x <= 11.9.1, 11.8.x <= 11.8.5, 11.7.x <= 11.7.10 fail to validate the target post ID in the Agents plugin's mention reminder component, which allows an authenticated user who can post in a channel visible to a system administrator to cause the administrator's browser to send an unintended API request, resulting in replacement of an installed plugin and code execution on the server, via a crafted post containing a forged mention reminder that the administrator clicks. Mattermost Advisory ID: MMSA-2026-00742

Weakness Classification (1)

Affected Software (1)

VendorProductVersion
Mattermost Mattermost 11.9.0

References & Advisories (1)

Bug Bounty Relevance

46 / 100
✓ Network accessible

CVSS Score

8.0 / 10.0 v3.1
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:H

EPSS — Exploitation Probability

0.27%
Raw Score 0.002660
Percentile 18.8%
Date 2026-10-29

Intelligence Sources

mitre ref →
nvd ref →

External Links