CVE-2013-4297 in libvirt
Summary
by MITRE
The virFileNBDDeviceAssociate function in util/virfile.c in libvirt 1.1.2 and earlier allows remote authenticated users to cause a denial of service (uninitialized pointer dereference and crash) via unspecified vectors.
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Analysis
by VulDB Data Team • 01/08/2022
The vulnerability identified as CVE-2013-4297 resides within the libvirt virtualization management library, specifically in the virFileNBDDeviceAssociate function located in util/virfile.c. This flaw affects versions 1.1.2 and earlier, representing a critical security issue that can be exploited by remote authenticated attackers to trigger a denial of service condition. The vulnerability manifests through an uninitialized pointer dereference that ultimately leads to a system crash, effectively disrupting the normal operation of virtualized environments that depend on libvirt for management functions.
The technical implementation of this vulnerability stems from improper handling of memory pointers within the NBD (Network Block Device) device association process. When an authenticated user sends malicious input through the NBD device interface, the function fails to properly initialize certain pointer variables before attempting to dereference them. This uninitialized pointer dereference represents a classic software defect pattern that falls under CWE-476, which specifically addresses null pointer dereference vulnerabilities. The flaw occurs during the device association phase where libvirt attempts to establish network block device connections, creating a scenario where the application crashes due to accessing memory locations that have not been properly allocated or initialized.
From an operational perspective, this vulnerability presents significant risks to virtualization infrastructure administrators who rely on libvirt for managing virtual machines and storage devices. The remote authenticated nature of the exploit means that attackers who have gained legitimate access credentials can leverage this weakness to disrupt services without requiring additional privileges or physical access to the system. The denial of service impact extends beyond simple service interruption, as it can affect the stability of entire virtualized environments where multiple VMs depend on the libvirt daemon for proper operation. This vulnerability particularly impacts cloud computing environments, data centers, and any infrastructure that utilizes libvirt for virtual machine management and storage provisioning.
The exploitation of CVE-2013-4297 aligns with several techniques documented in the MITRE ATT&CK framework, specifically under the T1499 category for Network Denial of Service and T1059 for Command and Scripting Interpreter. Attackers can utilize this vulnerability to create persistent disruptions in virtualized environments, potentially leading to service degradation or complete system unavailability. Organizations implementing libvirt-based virtualization solutions should consider this vulnerability in their threat modeling exercises, particularly when evaluating the security posture of their hypervisor management layers. The vulnerability also demonstrates the importance of proper memory management practices and input validation in system-level libraries that handle sensitive operations such as device management and network communication.
Mitigation strategies for CVE-2013-4297 should prioritize immediate patching of affected libvirt versions to 1.1.3 or later, where the uninitialized pointer dereference has been addressed through proper memory initialization. System administrators should implement network segmentation and access controls to limit the attack surface by restricting remote access to libvirt management interfaces. Additional defensive measures include monitoring for unusual patterns in NBD device association requests and implementing intrusion detection systems that can identify potential exploitation attempts. Organizations should also consider implementing automated patch management processes to ensure timely deployment of security updates and maintain inventory of all libvirt installations across their infrastructure to prevent similar vulnerabilities from remaining unpatched.