CVE-2025-12419 - CVE House
Back to Database
Status published Critical CVE-2025-12419

Account takeover on OAuth/OpenID-enabled servers

Vulnerability 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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

THREAT MONITOR

Am I Vulnerable?

Launch our assessment wizard to check if your infrastructure is exposed to • CVE-2025-12419

Credits & Attribution

The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:

  • daw10

References

More from Mattermost

View All →
CVE-2025-9084
Open redirect in OAuth login
Low 3.1
CVE-2025-9081
IDOR in board file download allows any user to download any file by UUID
Low 3.1
CVE-2025-9079
Admin RCE via prepackaged plugins by way of misconfigured imports directory
High 8
CVE-2025-9078
Weak cache keys lead to post IDOR and link preview poisoning
Medium 4.3
CVE-2025-9076
Mattermost Server exposes sensitive user credentials during shared channel membership synchronization
Medium 6.5

Affected Vendor

Affected Software

Mattermost
Vulnerable Versions:
10.12.0, 10.11.0, 10.5.0, 11.0.0, 11.1.0, 10.12.2, 10.11.5, 10.5.13, 11.0.4

Timeline

Official Publish: November 27th, 2025
Last Modified: February 26th, 2026
Added to House: July 22nd, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Weaknesses (CWE)

CWE-303

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.