CVE-2011-2011 in Windows
Summary
by MITRE
Use-after-free vulnerability in win32k.sys in the kernel-mode drivers in Microsoft Windows XP SP2 and SP3, Windows Server 2003 SP2, Windows Vista SP2, Windows Server 2008 SP2, R2, and R2 SP1, and Windows 7 Gold and SP1 allows local users to gain privileges via a crafted application that leverages incorrect driver object management, aka "Win32k Use After Free Vulnerability."
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Analysis
by VulDB Data Team • 02/02/2025
The CVE-2011-2011 vulnerability represents a critical use-after-free flaw in the win32k.sys kernel-mode driver component of Microsoft Windows operating systems. This vulnerability affects a broad range of Microsoft Windows versions including Windows XP SP2 and SP3, Windows Server 2003 SP2, Windows Vista SP2, Windows Server 2008 SP2 and R2, and Windows 7 Gold and SP1. The flaw resides in the kernel-mode driver responsible for managing user interface components and graphics operations, making it particularly dangerous as it operates at the highest privilege level within the operating system. The vulnerability stems from improper management of driver object references, where memory allocated to driver objects is freed but not properly dereferenced, creating opportunities for malicious code to exploit the dangling pointer.
The technical implementation of this vulnerability involves a specific scenario where a malicious application can manipulate the win32k.sys driver to trigger a use-after-free condition through improper handling of driver object references. When the driver processes certain user interface operations, it may free memory associated with a driver object while still maintaining references to that memory location. An attacker can then craft a malicious application that allocates new data structures at the same memory location previously freed by the driver, allowing them to control the execution flow of the kernel-mode driver. This exploitation technique aligns with the CWE-416 identifier for use-after-free vulnerabilities and represents a classic example of improper resource management in kernel-mode components. The vulnerability specifically targets the Windows kernel-mode graphics subsystem and leverages the inherent trust placed in legitimate system components to execute arbitrary code with kernel-level privileges.
The operational impact of CVE-2011-2011 is severe and far-reaching, as successful exploitation allows local users to achieve privilege escalation from standard user context to SYSTEM level access. This privilege escalation capability enables attackers to bypass standard security controls, access sensitive system files, modify system configurations, and potentially establish persistent backdoors within the compromised system. The vulnerability's exploitation does not require network connectivity or remote access, making it particularly dangerous as it can be leveraged through local malicious applications or compromised legitimate software. From an attacker's perspective, this vulnerability provides a reliable path to system compromise without requiring complex social engineering or additional attack vectors. The impact extends beyond individual system compromise to potentially enable lateral movement within network environments, as attackers with SYSTEM-level access can leverage other vulnerabilities or weaknesses in the broader network infrastructure.
Mitigation strategies for CVE-2011-2011 should focus on immediate patch management and system hardening approaches. Microsoft released security updates addressing this vulnerability through Windows Update, and organizations must ensure all affected systems receive these patches promptly. The vulnerability's exploitation requires local access, making user access control and application whitelisting important defensive measures. System administrators should implement the principle of least privilege, ensuring users operate with minimal required permissions. Additionally, implementing kernel-mode exploit protection mechanisms such as Data Execution Prevention and Address Space Layout Randomization can significantly reduce the exploitability of this vulnerability. Network segmentation and monitoring for suspicious local activity can help detect potential exploitation attempts. From an ATT&CK framework perspective, this vulnerability maps to privilege escalation techniques and leverages the T1068 tactic for local privilege escalation, making it particularly relevant for security teams focusing on kernel-level defenses and exploit prevention measures. Organizations should also consider implementing endpoint detection and response solutions that can identify suspicious driver behavior patterns associated with use-after-free exploitation attempts.