OAuth State Token Vulnerability in Mattermost by Mattermost
CVE-2025-12419

9.9CRITICAL

Key Information:

Vendor

Mattermost
Status
Mattermost
Vendor
CVE Published:
27 November 2025

What is CVE-2025-12419?

Mattermost's failure to validate OAuth state tokens during OpenID Connect authentication exposes it to the risk of account takeovers. Authenticated users with team creation or admin privileges could exploit this vulnerability by manipulating the authentication data in the OAuth completion flow, thereby gaining unauthorized access to any user account.

Affected Version(s)

Mattermost 10.12.0 <= 10.12.1

Mattermost 10.11.0 <= 10.11.4

Mattermost 10.5.0 <= 10.5.12

References

https://mattermost.com/security-updates

CVSS V3.1

Score:
9.9
Severity:
CRITICAL
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
Low
User Interaction:
None
Scope:
Changed

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

daw10
JSON
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