CVE-2014-4113 in Windows
Summary
by MITRE
win32k.sys in the kernel-mode drivers in Microsoft Windows Server 2003 SP2, Windows Vista SP2, Windows Server 2008 SP2 and R2 SP1, Windows 7 SP1, Windows 8, Windows 8.1, Windows Server 2012 Gold and R2, and Windows RT Gold and 8.1 allows local users to gain privileges via a crafted application, as exploited in the wild in October 2014, aka "Win32k.sys Elevation of Privilege Vulnerability."
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Analysis
by VulDB Data Team • 04/22/2026
The CVE-2014-4113 vulnerability represents a critical privilege escalation flaw in the Windows kernel-mode driver win32k.sys which forms the core of the Windows graphical subsystem. This vulnerability specifically affects multiple versions of Microsoft Windows including server and client operating systems from Windows vista through Windows 8.1, making it one of the most widely impacted privilege escalation vulnerabilities in recent Windows history. The flaw enables local attackers to elevate their privileges from standard user level to SYSTEM level, effectively granting them complete control over the affected system. The vulnerability was actively exploited in the wild during October 2014, demonstrating its real-world impact and the urgency of addressing such kernel-level flaws.
The technical nature of this vulnerability stems from improper validation of user-mode input within the win32k.sys driver, which handles windowing system operations and graphical user interface components. When a malicious application attempts to manipulate certain kernel-mode structures through the graphics subsystem, the driver fails to properly validate the input parameters, leading to memory corruption that can be exploited to execute arbitrary code with elevated privileges. This type of flaw falls under the CWE-121 category of "Stack-based Buffer Overflow" and specifically maps to the ATT&CK technique T1068 which describes "Exploitation for Privilege Escalation." The vulnerability is particularly dangerous because it operates within the kernel context where all system protections are effectively bypassed, allowing attackers to manipulate system memory directly without being constrained by user-mode security boundaries.
The operational impact of CVE-2014-4113 extends far beyond simple privilege escalation, as it provides attackers with complete system compromise capabilities. Once an attacker achieves SYSTEM level privileges through this vulnerability, they can install rootkits, modify system files, access all user data, and establish persistent backdoors that are extremely difficult to detect and remove. The vulnerability's exploitation requires only local access to the target system, making it particularly concerning for organizations with less stringent physical security controls. The fact that this vulnerability was actively exploited in the wild during 2014 indicates that attackers had developed reliable exploitation techniques that could be deployed against unpatched systems. Organizations running affected versions of Windows were particularly vulnerable as the exploitation chain required no network connectivity and could be executed through malicious applications that users might legitimately run, such as email attachments or downloaded software.
Mitigation strategies for CVE-2014-4113 primarily involve applying the relevant Microsoft security updates that address the underlying kernel-mode flaw in win32k.sys. Organizations should prioritize patching all affected Windows versions including Windows Server 2003, Windows Vista, Windows 7, Windows 8, and Windows RT systems. Additionally, implementing application whitelisting policies can help prevent exploitation by blocking malicious applications from executing, while monitoring for unusual kernel-mode activity can help detect exploitation attempts. The vulnerability's nature as a kernel-mode privilege escalation flaw makes it particularly resistant to traditional endpoint protection solutions, requiring system-level security controls and proactive patch management to provide effective defense. Organizations should also consider implementing the principle of least privilege and restricting local user account permissions to minimize the potential impact of successful exploitation attempts. Security teams should monitor for indicators of compromise related to this vulnerability through system logs, memory dumps, and network monitoring to detect any exploitation attempts against their environments.