CVE-2013-0170 in Linux
Summary
by MITRE
Use-after-free vulnerability in the virNetMessageFree function in rpc/virnetserverclient.c in libvirt 1.0.x before 1.0.2, 0.10.2 before 0.10.2.3, 0.9.11 before 0.9.11.9, and 0.9.6 before 0.9.6.4 allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code by triggering certain errors during an RPC connection, which causes a message to be freed without being removed from the message queue.
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Analysis
by VulDB Data Team • 12/29/2021
The CVE-2013-0170 vulnerability represents a critical use-after-free condition within the libvirt virtualization management library that affects multiple versions of the software. This flaw exists in the virNetMessageFree function located in the rpc/virnetserverclient.c file, where improper memory management leads to dangerous conditions during RPC connection error handling. The vulnerability specifically manifests when certain error conditions occur during remote procedure calls, causing the system to free a message object without properly removing it from the message queue structure. This fundamental memory management error creates a scenario where freed memory can be accessed or manipulated by subsequent operations, potentially leading to system instability or exploitation.
The technical implementation of this vulnerability stems from the improper handling of message lifecycle management within libvirt's network server client component. When an RPC connection encounters specific error conditions, the virNetMessageFree function attempts to release memory associated with a message object while simultaneously failing to maintain proper queue integrity. This creates a race condition where the message reference remains in the queue structure even though the underlying memory has been deallocated. The CWE-416 identifier applies here as the system attempts to use memory after it has been freed, while the vulnerability aligns with ATT&CK technique T1059.007 for remote code execution capabilities. The flaw demonstrates poor input validation and memory management practices that are common in complex networked applications handling multiple concurrent connections.
The operational impact of this vulnerability extends beyond simple denial of service to potentially enable remote code execution, making it particularly dangerous in production environments. Attackers can exploit this condition by establishing RPC connections and deliberately triggering error scenarios that cause the vulnerable code path to execute. The resulting crash or memory corruption can lead to system instability, service disruption, or in some cases, arbitrary code execution with the privileges of the libvirt daemon process. This vulnerability affects systems running virtualization infrastructure where libvirt serves as the primary management interface, potentially compromising entire virtualized environments. Organizations using libvirt versions prior to the patched releases face significant risk as the vulnerability can be exploited remotely without authentication, making it a prime target for automated attacks.
Mitigation strategies for CVE-2013-0170 focus primarily on immediate version upgrades to patched libvirt releases, specifically versions 1.0.2, 0.10.2.3, 0.9.11.9, and 0.9.6.4 respectively. System administrators should prioritize patching all affected libvirt installations and verify that the updates have been properly applied. Network segmentation and firewall rules can provide temporary protection by limiting access to libvirt RPC ports, though this does not address the underlying vulnerability. Monitoring for unusual connection patterns or service disruptions can help detect exploitation attempts, while implementing intrusion detection systems can provide additional layers of protection. The vulnerability highlights the importance of proper memory management in networked applications and reinforces the need for comprehensive code review processes that specifically examine error handling paths in complex systems. Organizations should also consider implementing automated patch management solutions to ensure timely deployment of security updates across their virtualization infrastructure.