Keycloak: oauth client impersonation

5.5 CVSS

Vulnerability Description

A flaw was found in Keycloak. A Keycloak server configured to support mTLS authentication for OAuth/OpenID clients does not properly verify the client certificate chain. A client that possesses a proper certificate can authorize itself as any other client, therefore, access data that belongs to other clients.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

Red Hat

View all reports →

Affected Software

Red Hat Single Sign-On 7, Red Hat Single Sign-On 7.6 for RHEL 7, Red Hat Single Sign-On 7.6 for RHEL 8, Red Hat Single Sign-On 7.6 for RHEL 9, RHEL-8 based Middleware Containers

Vulnerable Versions:

0:18.0.8-1.redhat_00001.1.el7sso, 0:18.0.8-1.redhat_00001.1.el8sso, 0:18.0.8-1.redhat_00001.1.el9sso, 7.6-24