CVE-2012-4556 in Certificate System
Summary
by MITRE
The token processing system (pki-tps) in Red Hat Certificate System (RHCS) before 8.1.3 allows remote attackers to cause a denial of service (Apache httpd web server child process restart) via certain unspecified empty search fields in a user certificate search query.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 12/21/2021
The vulnerability identified as CVE-2012-4556 affects the token processing system component known as pki-tps within Red Hat Certificate System versions prior to 8.1.3. This issue represents a significant security weakness in the certificate management infrastructure that could be exploited by remote attackers to disrupt service availability. The vulnerability specifically targets the Apache httpd web server child processes that handle user certificate search queries, creating a potential vector for denial of service attacks that could compromise the overall certificate infrastructure.
The technical flaw manifests when the pki-tps system processes user certificate search queries containing unspecified empty search fields. These empty fields trigger an unexpected behavior in the token processing system that causes the underlying Apache httpd web server child processes to restart automatically. This restart mechanism represents a critical design weakness in the input validation and error handling mechanisms of the certificate system. The vulnerability operates at the application layer and leverages the inherent architecture of the web server to create a cascading effect that consumes system resources and disrupts legitimate service operations.
The operational impact of this vulnerability extends beyond simple service disruption, as it can effectively render the certificate management system unavailable to legitimate users and applications. When Apache httpd child processes restart due to malformed search queries, the system experiences temporary unavailability while processes are recycled, potentially affecting certificate issuance, revocation, and validation services. This disruption can have cascading effects throughout enterprise environments that depend on certificate-based authentication and encryption services, particularly in scenarios where certificate authorities are critical infrastructure components for secure communications and identity management.
From a cybersecurity perspective, this vulnerability aligns with CWE-20, which describes improper input validation, and demonstrates characteristics consistent with attack patterns documented in the MITRE ATT&CK framework under the privilege escalation and denial of service categories. The remote exploitation aspect means that attackers do not require physical access or elevated privileges to trigger the vulnerability, making it particularly dangerous in networked environments. Organizations using affected versions of Red Hat Certificate System should implement immediate mitigations including upgrading to version 8.1.3 or later, implementing network-level filtering to restrict access to certificate search endpoints, and deploying monitoring solutions to detect anomalous search query patterns that could indicate exploitation attempts.
The vulnerability highlights the importance of robust input validation and error handling in security-critical systems, particularly those managing cryptographic certificates and tokens. Proper sanitization of user inputs and implementation of defensive programming practices could prevent the exploitation of such weaknesses. Organizations should also consider implementing rate limiting and access controls for certificate search functionality to reduce the attack surface and minimize the potential impact of similar vulnerabilities in the future. The remediation process should include thorough testing of the updated system to ensure that the fix does not introduce new compatibility issues while maintaining the integrity of certificate management operations.