Description

Mattermost versions 11.0.x <= 11.0.2, 10.12.x <= 10.12.1, 10.11.x <= 10.11.4, 10.5.x <= 10.5.12 fail to to verify that the token used during the code exchange originates from the same authentication flow, which allows an authenticated user to perform account takeover via a specially crafted email address used when switching authentication methods and sending a request to the /users/login/sso/code-exchange endpoint. The vulnerability requires ExperimentalEnableAuthenticationTransfer to be enabled (default: enabled) and RequireEmailVerification to be disabled (default: disabled).

INFO

Published Date :

2025-11-27T17:47:04.944Z

Last Modified :

2025-11-27T17:47:04.944Z

Source :

Mattermost
AFFECTED PRODUCTS

The following products are affected by CVE-2025-12421 vulnerability.

No data.

REFERENCES

Here, you will find a curated list of external links that provide in-depth information to CVE-2025-12421.

CVSS Vulnerability Scoring System

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