CVE-2015-2534 in Windows
Summary
by MITRE
Hyper-V in Microsoft Windows 8.1, Windows Server 2012 R2, and Windows 10 improperly processes ACL settings, which allows local users to bypass intended network-traffic restrictions via a crafted application, aka "Hyper-V Security Feature Bypass Vulnerability."
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Analysis
by VulDB Data Team • 11/27/2024
The CVE-2015-2534 vulnerability represents a critical security flaw in Microsoft Hyper-V virtualization components affecting Windows 8.1, Windows Server 2012 R2, and Windows 10 systems. This vulnerability stems from improper handling of Access Control List (ACL) settings within the Hyper-V hypervisor implementation, creating a significant bypass opportunity for local attackers. The flaw specifically targets the security mechanisms designed to restrict network traffic between virtual machines and host systems, effectively undermining the isolation properties that virtualization environments rely upon for security containment.
The technical root cause of this vulnerability lies in the manner Hyper-V processes and validates ACL configurations during virtual machine network interface operations. When a local user executes a crafted application, the vulnerability allows the attacker to manipulate the hypervisor's network traffic filtering mechanisms, bypassing the intended security boundaries that should prevent unauthorized communication between virtual machines and the host system. This improper ACL handling creates a privilege escalation path where local users can circumvent network restrictions that were designed to maintain compartmentalization between different virtualized environments.
From an operational perspective, this vulnerability presents a severe risk to enterprise environments where Hyper-V is extensively deployed for virtualization purposes. Local attackers who successfully exploit this vulnerability can potentially establish unauthorized network connections, access sensitive data from other virtual machines, or perform man-in-the-middle attacks against virtualized applications. The impact extends beyond simple privilege escalation as it fundamentally compromises the security model of virtualized environments, potentially allowing attackers to move laterally within networks where virtualization is used for security segmentation. This vulnerability particularly affects organizations that rely on Hyper-V for hosting multiple tenants or isolated workloads, as it undermines the core principle of virtual machine isolation.
The vulnerability aligns with CWE-284, which addresses improper access control mechanisms, and demonstrates characteristics consistent with ATT&CK technique T1068, which involves local privilege escalation through system flaws. Organizations should implement immediate mitigations including applying Microsoft security updates, reviewing Hyper-V network configuration settings, and implementing additional monitoring controls to detect unauthorized network access patterns. Network segmentation controls should be enhanced, and virtual machine network policies should be audited to ensure proper ACL enforcement. Additionally, security teams should consider implementing behavioral analytics to detect anomalous network traffic patterns that might indicate exploitation attempts, as this vulnerability can be leveraged for both reconnaissance and lateral movement within compromised virtualized environments.