MFA Enforcement Bypass Allows Unauthorized Removal of MFA for Other Users
Mattermost versions 10.5.x <= 10.5.1, 9.11.x <= 9.11.9 fail to enforce MFA checks in PUT /api/v4/users/user-id/mfa when the requesting user differs from the target user ID, which allows users with edit_other_users permission to activate or deactivate MFA for other users, even if those users have not set up MFA.
02 / AFFECTED SOFTWARE
Affected packages
35 explicit affected versions
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
Mattermost versions 10.5.x <= 10.5.1, 9.11.x <= 9.11.9 fail to enforce MFA checks in PUT /api/v4/users/user-id/mfa when the requesting user differs from the target user ID, which allows users with edit_other_users permission to activate or deactivate MFA for other users, even if those users have not set up MFA.
Mattermost Missing Authentication for Critical Function in github.com/mattermost/mattermost-server
Mattermost versions 10.5.x <= 10.5.1, 9.11.x <= 9.11.9 fail to enforce MFA checks in PUT /api/v4/users/user-id/mfa when the requesting user differs from the target user ID, which allows users with edit_other_users permission to activate or deactivate MFA for other users, even if those users have not set up MFA.
05 / REFERENCES
Further evidence
- https://github.com/mattermost/mattermost
- https://mattermost.com/security-updates
- https://nvd.nist.gov/vuln/detail/CVE-2025-27538
- https://pkg.go.dev/vuln/GO-2025-3620
- https://github.com/advisories/GHSA-j5jw-m2ph-3jjf
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/27xxx/CVE-2025-27538.json