CVE-2016-3077 in oVirt Engine
Summary
by MITRE
The VersionMapper.fromKernelVersionString method in oVirt Engine allows remote authenticated users to cause a denial of service (process crash) for all VMs.
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Analysis
by VulDB Data Team • 10/14/2019
The vulnerability identified as CVE-2016-3077 resides within the oVirt Engine's VersionMapper.fromKernelVersionString method, representing a critical denial of service weakness that affects virtual machine operations. This flaw specifically targets the kernel version string parsing functionality within the oVirt management platform, which is widely used for virtualization orchestration in enterprise environments. The vulnerability manifests when remote authenticated users exploit improper input validation within the version mapping process, leading to process crashes that subsequently impact all virtual machines under the engine's management. The attack vector requires authentication credentials, making it a privilege escalation concern within the virtualization infrastructure rather than a direct public exploit.
The technical implementation of this vulnerability stems from inadequate error handling and input sanitization within the VersionMapper component. When the fromKernelVersionString method processes malformed or unexpected kernel version strings, the parsing logic fails to properly validate input parameters, resulting in unhandled exceptions that cause the oVirt Engine process to terminate abruptly. This process crash creates cascading effects throughout the virtualization environment, as all managed virtual machines lose their connection to the engine and become inaccessible to users and administrators. The vulnerability operates at the application layer, specifically targeting the engine's version compatibility mapping system that is essential for maintaining proper virtual machine operations and resource allocation.
From an operational impact perspective, CVE-2016-3077 represents a significant threat to virtualization infrastructure stability and business continuity. The denial of service condition affects not just individual virtual machines but the entire oVirt Engine instance, potentially disrupting critical business applications that depend on virtualized environments. This vulnerability aligns with CWE-20, "Improper Input Validation," and CWE-400, "Uncontrolled Resource Consumption," as it allows authenticated users to consume system resources in an uncontrolled manner leading to process termination. The impact extends beyond simple service disruption to include potential data loss scenarios where virtual machines cannot be properly shut down or migrated during the engine crash event.
The exploitability of this vulnerability requires an authenticated user account within the oVirt environment, which limits its scope to internal threats or compromised user credentials. However, this authentication requirement does not diminish the severity of the impact, as it allows for targeted attacks against specific virtualization environments. The vulnerability's characteristics align with ATT&CK technique T1499.001, "Network Denial of Service," and T1566.002, "Phishing," as it can be leveraged through social engineering to obtain user credentials or through legitimate administrative access to cause service disruption. Organizations implementing oVirt Engine solutions must consider this vulnerability as part of their security posture assessment, particularly in environments where privileged user accounts are not adequately protected or monitored.
Mitigation strategies for CVE-2016-3077 should focus on both immediate patching and enhanced monitoring of the oVirt Engine environment. The primary solution involves applying the vendor-provided security update that addresses the improper input validation in the VersionMapper.fromKernelVersionString method. Additionally, implementing strict access controls and monitoring for unusual authentication patterns can help detect potential exploitation attempts. Organizations should also consider implementing process monitoring tools that can automatically restart the oVirt Engine service if crashes occur, reducing the impact duration. Network segmentation and least privilege principles should be enforced to limit the potential scope of exploitation, ensuring that only authorized personnel have access to the virtualization management interfaces where this vulnerability can be leveraged for denial of service attacks.