Moole Vulnerability Database

Find real vulnerabilities before they ship

Medium

CVE-2026-0999

Mattermost versions 11.1.x <= 11.1.2, 10.11.x <= 10.11.9, 11.2.x <= 11.2.1 fail to properly validate login method restrictions which allows an authenticated user to bypass SSO-only login requirements via userID-based authentication. Mattermost Advisory ID: MMSA-2025-00548

VectorNETWORK

PublishedFeb 16, 2026, 10:16

Published Byresponsibledisclosure@mattermost.com

Base Score

Score4.3

Affected Versions

Package (Ecosystem)IntroducedFixedLimit

github.com/mattermost/mattermost/server/v8(Go)08.0.0-20251212052346-61651b0df7eaN/A

github.com/mattermost/mattermost-server(Go)11.1.0N/AN/A

github.com/mattermost/mattermost-server(Go)10.11.0N/AN/A

github.com/mattermost/mattermost-server(Go)11.2.0N/AN/A

github.com/mattermost/mattermost-server(Go)05.3.2-0.20251212052346-61651b0df7eaN/A

References

https://mattermost.com/security-updates

Weakness Type

CWE-303

CVSS Metrics

Base Score

4.3

Vector String

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N

Base SeverityMedium

Version

3.1

Attack Vector (AV)

NETWORK