CVE-2026-79812 in ClearPass Policy Manager
Summary
by MITRE • 10/06/2026
A denial of service vulnerability exists in the OnGuard agent of HPE Networking ClearPass Policy Manager. Successful exploitation could allow an authenticated local attacker to interrupt the normal operation of the agent service.
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Analysis
by VulDB Data Team • 10/07/2026
The identified security issue resides within the OnGuard agent component of Hewlett Packard Enterprise (HPE) Networking ClearPass Policy Manager, a critical platform used for network access control and policy enforcement. This vulnerability is classified as a denial of service condition that specifically targets the operational stability of the local agent service. The nature of this flaw indicates a failure in input validation or resource management within the OnGuard software module, which serves to monitor endpoint compliance with security policies before granting network access. When an attacker successfully exploits this weakness, they can trigger conditions that cause the agent process to crash, hang, or become unresponsive, thereby halting its ability to perform essential health checks and policy evaluations for connected devices.
The exploitation vector requires authentication as a local user on the system where ClearPass Policy Manager is installed. This constraint implies that an attacker must already have valid credentials with sufficient privileges to interact with the OnGuard service interface or execute commands within the operating environment of the server. While this requirement limits the attack surface compared to remote unauthenticated exploits, it remains significant in environments where insider threats exist or where credential theft has occurred through other means such as phishing or lateral movement from a compromised workstation. The ability for an authenticated local attacker to disrupt service operations highlights a lack of proper privilege separation or sandboxing within the application architecture, allowing lower-privileged processes to impact core security functions.
From an operational perspective, the successful exploitation results in a significant degradation of network security posture. Since OnGuard is responsible for verifying endpoint compliance with organizational policies before granting access to protected resources, its failure creates a blind spot in the network defense strategy. During the period when the agent service is interrupted, devices may be incorrectly assessed as compliant or non-compliant depending on how the ClearPass server handles the loss of heartbeat signals from the agent. This can lead to either unauthorized access by potentially malicious endpoints that fail health checks but are not detected due to communication failure, or legitimate users being denied network connectivity unnecessarily. The impact extends beyond mere service interruption to include potential data integrity issues and operational downtime for IT administrators who rely on accurate endpoint visibility.
This vulnerability aligns with Common Weakness Enumeration (CWE) category CWE-400, which describes uncontrolled resource consumption leading to denial of service conditions. It also relates to CWE-269 regarding improper privilege escalation if the local authentication requirement is bypassed through other means, though primarily it represents a failure in robust error handling and state management within the application logic. In terms of the MITRE ATT&CK framework, this behavior corresponds to techniques under the Impact tactic, specifically resource hijacking or service stoppage, which adversaries use to disrupt availability as part of their operational goals. The lack of adequate safeguards against local denial of service attacks underscores a need for improved defensive coding practices and stricter isolation mechanisms within enterprise security software components.
To mitigate this risk, organizations should ensure that the HPE ClearPass Policy Manager is updated to the latest version provided by Hewlett Packard Enterprise, which likely includes patches addressing these stability issues in the OnGuard agent. Administrators should enforce strict access controls on the management servers hosting ClearPass, ensuring that only essential administrative accounts have local login privileges and that multi-factor authentication is required for such access. Additionally, implementing network segmentation to isolate critical security infrastructure from general user networks can reduce the attack surface available to potential intruders who might gain initial footholds elsewhere in the environment. Regular auditing of service health and monitoring for unusual resource consumption patterns by system processes can also aid in early detection of exploitation attempts or instability within the OnGuard component, allowing for rapid remediation before significant operational disruption occurs.