PT-2026-25813 · Mattermost · Mattermost

Hackit_Bharat · Published 2026-03-16 · Updated 2026-03-16 · CVE-2026-26230

NVD

CVSS v3.1

3.8

3.8

Low

Base vector

AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:N

Mattermost versions 10.11.x <= 10.11.10 fail to properly validate permission requirements in the team member roles API endpoint which allows team administrators to demote members to guest role. Mattermost Advisory ID: MMSA-2025-00531

Fix

Incorrect Authorization

Weakness Enumeration

CWE-863

Related Identifiers

CVE-2026-26230

Affected Products

Mattermost

References · 2

• https://nvd.nist.gov/vuln/detail/CVE-2026-26230 · Security Note
• https://mattermost.com/security-updates · Vendor Advisory