CVE-2014-2599 in Xen
Summary
by MITRE
The HVMOP_set_mem_access HVM control operations in Xen 4.1.x for 32-bit and 4.1.x through 4.4.x for 64-bit allow local guest administrators to cause a denial of service (CPU consumption) by leveraging access to certain service domains for HVM guests and a large input.
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Analysis
by VulDB Data Team • 05/09/2026
The vulnerability identified as CVE-2014-2599 represents a critical denial of service flaw within the Xen hypervisor implementation that affects multiple versions across different architectures. This issue specifically targets the HVMOP_set_mem_access hypercall operation which is part of the HVM control operations designed to manage memory access permissions for HVM (Hardware Virtual Machine) guests. The vulnerability is particularly concerning because it can be exploited by local guest administrators who possess access to certain service domains, making it a significant threat within virtualized environments where guest isolation is paramount for security.
The technical flaw manifests through improper input validation and handling within the HVMOP_set_mem_access operation. When a malicious guest administrator submits a large input parameter to this hypercall, the hypervisor fails to adequately process or limit the resource consumption associated with the operation. This results in excessive CPU utilization as the hypervisor attempts to handle the malformed input, effectively consuming system resources and potentially causing a denial of service condition that affects the entire host system. The vulnerability affects both 32-bit systems running Xen 4.1.x and 64-bit systems running Xen 4.1.x through 4.4.x, indicating a widespread impact across the affected version ranges.
The operational impact of this vulnerability extends beyond simple resource exhaustion, as it represents a serious breach of hypervisor isolation principles that are fundamental to virtualization security. Attackers can leverage this weakness to consume excessive CPU cycles, potentially causing legitimate guest instances to experience performance degradation or complete unresponsiveness. The vulnerability is particularly dangerous because it allows local privilege escalation within the guest environment to achieve a broader impact on the host system, violating the core security assumption that guest instances cannot directly compromise host resources. This flaw directly relates to CWE-770, which describes allocation of resources without limits or proper checking, and aligns with ATT&CK technique T1499.001 for Resource Exhaustion.
Mitigation strategies for CVE-2014-2599 should focus on immediate patching of affected Xen versions, with administrators upgrading to patched releases that properly validate input parameters for the HVMOP_set_mem_access hypercall. System administrators should implement strict access controls and monitoring to detect unusual CPU consumption patterns that might indicate exploitation attempts. The vulnerability demonstrates the importance of proper input validation in hypervisor code and highlights the need for comprehensive security testing of hypercall interfaces. Organizations should also consider implementing additional monitoring mechanisms to track resource usage patterns and establish baseline behaviors for normal system operation, as this vulnerability can be used as a stealthy method of resource exhaustion that might go unnoticed in poorly monitored environments.