CVE-2025-12419

Account takeover on OAuth/OpenID-enabled servers

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.

We have discovered 62 live websites that are affected by CVE-2025-12419.

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Affected Software

Product  Mattermost
Category Message Boards
Vulnerable Domains62 live websites (15% of Mattermost install base)
Vulnerable Versions
  • from 10.5 through 10.5.12
  • from 10.11 through 10.11.4
  • from 10.12 through 10.12.1
  • from 11 through 11.0.3
Vulnerable Versions Count10 versions ( 15% of all versions)


Common Weakness Enumeration

CWE-303 Incorrect Implementation of Authentication Algorithm



Details

  • Published - Nov 27, 2025
  • Updated - Feb 26, 2026

Credits

  • daw10 (finder)

Website Distribution by Country

Number of websites using CVE-2025-12419
United States13 websites


Germany23 websites
GB9 websites
France3 websites
Czech Republic2 websites
Russia2 websites
Turkmenistan2 websites
Austria1 websites
Canada1 websites

Website Distribution by TLD

Number of websites using CVE-2025-12419
.org14 websites
.com13 websites
.de11 websites
.ru4 websites
.co.uk2 websites
.fr2 websites
.info2 websites
.net2 websites
.io1 websites
.pl1 websites

Vulnerable Versions

Vulnerable versions are highlighted in red

Websites affected by CVE-2025-12419

Top websites that are affected by CVE-2025-12419. Please click on the "Contact us" link to get more information.
DomainCountryRankContacts
***********.com Germany***,***
****.*******.com GB***,***
****.*******.org Germany*,***,***
***********.ru Russia*,***,***
****.*******.com Germany*,***,***
****.*********.org United States*,***,***
****.**************.de Germany*,***,***
*****.*************.org GB*,***,***
*******.org Germany*,***,***
******.*************.org GB**,***,***
See full domain list

FAQ

CVE-2025-12419 is Incorrect Implementation of Authentication Algorithm in Mattermost
A total of 62 websites have been identified as vulnerable to CVE-2025-12419, based on global website indexing conducted by WebTechSurvey.
The Mattermost is affected by the CVE-2025-12419 vulnerability.
Mattermost versions up to and including 11.0.3 are vulnerable to CVE-2025-12419.