CVE-2016-5404 in FreeIPA
Summary
by MITRE
The cert_revoke command in FreeIPA does not check for the "revoke certificate" permission, which allows remote authenticated users to revoke arbitrary certificates by leveraging the "retrieve certificate" permission.
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Analysis
by VulDB Data Team • 09/26/2024
The vulnerability identified as CVE-2016-5404 resides within the FreeIPA certificate management system, specifically in the cert_revoke command implementation. This flaw represents a critical authorization bypass that undermines the security controls designed to protect certificate lifecycle management within enterprise identity infrastructure. FreeIPA serves as a comprehensive identity management solution that combines identity federation, certificate management, and access control mechanisms, making this vulnerability particularly concerning for organizations relying on its certificate authority services.
The technical flaw manifests as a missing permission check within the certificate revocation process. When an authenticated user attempts to revoke a certificate through the cert_revoke command, the system fails to validate whether the user possesses the necessary "revoke certificate" permission. Instead, the system only verifies the presence of the "retrieve certificate" permission, which is typically granted to users who need to view certificate information but not to modify certificate status. This oversight creates a privilege escalation path where users with limited certificate access can perform destructive actions beyond their intended authorization scope.
The operational impact of this vulnerability extends beyond simple unauthorized certificate revocation. Attackers leveraging this flaw can potentially disrupt certificate-based authentication systems, compromise secure communications, and undermine the integrity of the entire certificate authority infrastructure. In enterprise environments where FreeIPA manages thousands of certificates for various services, this vulnerability could enable attackers to cause widespread service disruption by revoking critical certificates. The attack vector requires only remote authentication access and does not necessitate elevated privileges or complex exploitation techniques, making it particularly dangerous in environments where certificate management is frequently accessed by multiple user roles.
This vulnerability aligns with CWE-862, which describes insufficient authorization checks, and represents a classic case of privilege escalation through improper access control validation. From an ATT&CK framework perspective, this flaw maps to privilege escalation techniques where adversaries leverage existing permissions to gain unauthorized access to additional resources. The vulnerability also demonstrates weaknesses in the principle of least privilege implementation, where certificate management operations should require specific authorization tokens rather than relying on broader permission sets that inadvertently grant unauthorized capabilities.
Organizations should implement immediate mitigations including patching the FreeIPA system to the latest stable release containing the permission validation fix, reviewing and restricting certificate management permissions within the system, and implementing additional monitoring for certificate revocation activities. Security teams should also consider implementing automated alerts for unauthorized certificate revocation attempts and conduct comprehensive audits of certificate management permissions to ensure that users only possess the minimum necessary privileges for their roles. The vulnerability highlights the critical importance of proper access control implementation in certificate management systems and serves as a reminder of the potential for seemingly minor permission gaps to create significant security risks in identity infrastructure solutions.