Confidential Containers Trustee Project Attestation Policy Authentication Bypass Vulnerability

An authentication bypass vulnerability has been identified in the Confidential Containers Trustee project, specifically in versions prior to 0.15.0. The issue arises in the attestation-policy endpoint, which failed to verify if the kbs-client making the request was authenticated. This oversight allowed any kbs-client to modify the attestation policy. The vulnerability has been addressed in version 0.15.0.

Impact

Exploitation of this vulnerability allowed unauthorized kbs-clients to change the attestation policy, potentially leading to unauthorized access or modification of sensitive operations within the Trustee framework.

Reproduction

To reproduce this vulnerability, send a request to the attestation-policy endpoint using an unverified kbs-client key. The request to change the attestation policy will be accepted, despite the lack of proper authentication.

Remediation

Users can upgrade to Trustee version 0.15.0 or later, where this vulnerability has been fixed.