CVE-2025-12421

Summary

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).

Affected Software

VendorProductVersion RangeStatus
MattermostMattermost11.0.0 <= 11.0.2affected
MattermostMattermost10.12.0 <= 10.12.1affected
MattermostMattermost10.11.0 <= 10.11.4affected
MattermostMattermost10.5.0 <= 10.5.12affected
MattermostMattermost11.1.0unaffected
MattermostMattermost11.0.3unaffected
MattermostMattermost10.12.2unaffected
MattermostMattermost10.11.5unaffected
MattermostMattermost10.5.13unaffected

Weaknesses

  • CWE-303: CWE-303: Incorrect Implementation of Authentication Algorithm

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: total

References