CVE-2026-0999GHSA-3C9R-7F29-QP32GO-2026-4520
Authentication bypass via userID login when email and username login are disabled
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 8.0.0-20251212052346-61651b0df7ea, 5.3.2-0.20251212052346-61651b0df7ea
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
CISA's decision points: whether it is exploited, whether attacks can be automated, and how much control an attacker gets. Assessed (SSVC 2.0.3).What do these mean? →
- Exploitation: none
- Automatable: no
- Technical impact: partial
Summary
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
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: partial
- Record last updated
Affected versions
- Mattermost Mattermost
From 11.1.0 · through 11.1.2; From 10.11.0 · through 10.11.9; From 11.2.0 · through 11.2.1
- github.com/mattermost/mattermost/server/v8Go
fixed in 8.0.0-20251212052346-61651b0df7ea
- github.com/mattermost/mattermost-serverGo
From 11.1.0
- github.com/mattermost/mattermost-serverGo
From 10.11.0
- github.com/mattermost/mattermost-serverGo
From 11.2.0
- github.com/mattermost/mattermost-serverGo
fixed in 5.3.2-0.20251212052346-61651b0df7ea
- github.com/mattermost/mattermost-serverGo
All versions
- github.com/mattermost/mattermost-serverGo
From 10.11.0+incompatible
- github.com/mattermost/mattermost-serverGo
From 11.1.0+incompatible
- github.com/mattermost/mattermost-serverGo
From 11.2.0+incompatible
- github.com/mattermost/mattermost-server/v5Go
All versions
- github.com/mattermost/mattermost-server/v6Go
All versions