CVE-2011-1878 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 SP1 and SP2, Windows Server 2008 Gold, 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, a different vulnerability than other CVEs listed in MS11-054, aka "Win32k Use After Free Vulnerability."
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Analysis
by VulDB Data Team • 11/14/2021
The CVE-2011-1878 vulnerability represents a critical use-after-free condition within the win32k.sys kernel-mode driver component of Microsoft Windows operating systems. This vulnerability exists in multiple Windows versions including XP SP2 and SP3, Windows Server 2003 SP2, Windows Vista SP1 and SP2, Windows Server 2008 Gold, SP2, R2, and R2 SP1, as well as Windows 7 Gold and SP1. The flaw stems from improper management of driver objects within the kernel-mode environment, specifically affecting the win32k.sys driver that handles user-mode graphics and windowing operations. This vulnerability is classified as a CWE-416 Use After Free weakness, which occurs when a program continues to reference memory after it has been freed, potentially leading to arbitrary code execution or privilege escalation.
The technical exploitation of this vulnerability requires a local attacker to craft a malicious application that can manipulate the win32k.sys driver's object management routines. When the vulnerable driver processes certain graphics or windowing operations, it fails to properly validate object references, creating a window where freed memory can be accessed and potentially overwritten. The attack vector leverages the kernel-mode execution context, allowing local users to escalate their privileges from standard user level to SYSTEM level access. This particular vulnerability differs from other issues addressed in MS11-054, indicating it operates through distinct code paths within the kernel driver subsystem.
The operational impact of CVE-2011-1878 is severe as it enables local privilege escalation attacks that can result in complete system compromise. An attacker with low-privilege access can potentially execute arbitrary code with kernel-level privileges, providing access to all system resources, files, and processes. The vulnerability affects the core windowing subsystem of Windows, making it particularly dangerous as it can be exploited through normal user interactions with graphical applications. This type of vulnerability is categorized under ATT&CK technique T1068, which covers 'Local Privilege Escalation' and specifically targets kernel-mode exploits. The exploitation process typically involves creating a malicious application that triggers the vulnerable code path, causing the driver to free memory that is subsequently accessed, leading to code execution.
Mitigation strategies for this vulnerability require immediate patching of affected systems through Microsoft security updates, particularly the MS11-054 patch which addresses this specific issue. System administrators should prioritize deployment of the security update across all affected Windows versions, as the vulnerability can be exploited without user interaction once the malicious application is launched. Additional protective measures include implementing least privilege principles, disabling unnecessary graphical features, and monitoring for suspicious kernel-mode activity. The vulnerability demonstrates the critical importance of kernel-mode security in operating system design, as flaws in core drivers can provide attackers with the most privileged execution context available. Organizations should also consider implementing application whitelisting and enhanced monitoring of kernel-mode operations to detect potential exploitation attempts. The vulnerability serves as a reminder of the complex security challenges inherent in kernel-mode drivers and the necessity for rigorous code review and security testing of system-critical components.