Is CVE-2025-12419 actively exploited?

No active exploitation of CVE-2025-12419 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2025-12419 be exploited remotely?

Yes. CVE-2025-12419 is exploitable remotely over the network (CVSS attack vector: Network).

What is the CVSS score of CVE-2025-12419?

CVE-2025-12419 has a CVSS score of 9.9 (CRITICAL).

HOME VULNERABILITIESCVE-2025-12419

CRITICAL

CVE-2025-12419

CWE-303Published: November 27, 2025· Updated: Jun 17, 2026

9.9

CVSS v3.1

Official 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.

NVD Source

Risk Analysis

This critical vulnerability in Mattermost allows an authenticated attacker with team creation privileges to take over user accounts. The issue stems from improper validation of OAuth state tokens during OpenID Connect authentication, enabling manipulation of authentication data. With a critical CVSS score of 9.9, this flaw poses a significant threat to user account security and data integrity.

No public exploit is currently known for this vulnerability. Exploitation requires specific conditions, including disabled email verification, enabled OAuth/OpenID Connect, and the attacker controlling two SSO users where one has never logged into Mattermost.

Recommended Action

Administrators should ensure email verification is enabled and apply any available patches or upgrades for Mattermost Server to versions beyond 10.12.1, 10.11.4, 10.5.12, and 11.0.3.

Generated by the CTIWATCH analysis pipeline from this CVE's metadata (CVSS, EPSS, KEV status, exploit intelligence). Verify against vendor advisories before acting.

Technical Analysis

CVE-2025-12419 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 9.9.

The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.