CVE-2026-0999 (GCVE-0-2026-0999)
Vulnerability from cvelistv5 – Published: 2026-02-16 09:47 – Updated: 2026-02-17 16:53
VLAI
EPSS
VEX
Title
Authentication bypass via userID login when email and username login are disabled
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
Severity
5.4 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-02-17 16:52 UTC
CWE
- CWE-303 - Incorrect Implementation of Authentication Algorithm
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://mattermost.com/security-updates | vendor-advisory |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Mattermost | Mattermost |
Affected:
11.1.0 , ≤ 11.1.2
(semver)
Affected: 10.11.0 , ≤ 10.11.9 (semver) Affected: 11.2.0 , ≤ 11.2.1 (semver) Unaffected: 11.3.0 Unaffected: 11.1.3 Unaffected: 10.11.10 Unaffected: 11.2.2 |
guessed |
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