CVE-2025-12419
Published: Nov 27, 2025
Modified: Feb 26, 2026
CVSS v3.1
9.9
Description
Mattermost versions 10.12.x <= 10.12.1, 10.11.x <= 10.11.4, 10.5.x <= 10.5.12, 11.0.x <= 11.0.3 fail to properly validate OAuth state tokens during OpenID Connect authentication which allows an authenticated attacker with team creation privileges to take over a user account via manipulation of authentication data during the OAuth completion flow. This requires email verification to be disabled (default: disabled), OAuth/OpenID Connect to be enabled, and the attacker to control two users in the SSO system with one of them never having logged into Mattermost.
| Vendor | Product | Versions |
|---|---|---|
Mattermost | Mattermost | affected 10.12.0 - <= 10.12.1affected 10.11.0 - <= 10.11.4affected 10.5.0 - <= 10.5.12affected 11.0.0 - <= 11.0.3unaffected 11.1.0+4 more versions |
Weaknesses (CWE)
CVSS v3.1 Details
CVSS v3.1 Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability
References
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