CVE-2015-2517 in Windows
Summary
by MITRE
The kernel-mode driver in Microsoft Windows Vista SP2, Windows Server 2008 SP2 and R2 SP1, Windows 7 SP1, Windows 8, Windows 8.1, Windows Server 2012 Gold and R2, Windows RT Gold and 8.1, and Windows 10 allows local users to gain privileges via a crafted application, aka "Win32k Memory Corruption Elevation of Privilege Vulnerability," a different vulnerability than CVE-2015-2511, CVE-2015-2518, and CVE-2015-2546.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 07/07/2025
The vulnerability identified as CVE-2015-2517 represents a critical privilege escalation flaw within the Windows kernel-mode driver subsystem, specifically affecting multiple versions of the microsoft windows operating system. This issue resides in the win32k.sys driver which manages user interface components and graphics rendering functions within the windows kernel space. The flaw enables local attackers with standard user privileges to execute malicious code that can elevate their access level to system-level privileges, effectively bypassing the operating system's security boundaries. The vulnerability is categorized under the common weakness enumeration cwe-119 as it involves improper handling of memory access patterns within kernel mode components. This particular weakness falls under the broader category of memory corruption vulnerabilities that can be exploited to manipulate program execution flow and gain unauthorized system access.
The technical mechanism behind this privilege escalation vulnerability stems from inadequate input validation and memory management within the win32k.sys driver. When processing certain graphics-related API calls or user interface operations, the driver fails to properly validate memory access parameters, creating opportunities for attackers to craft malicious applications that can manipulate kernel memory structures. This memory corruption allows attackers to overwrite critical kernel data structures or execute arbitrary code within the kernel context, fundamentally compromising the security model of the operating system. The vulnerability specifically relates to how the driver handles certain user-mode memory references during graphics rendering operations, creating a path for privilege escalation that does not require network connectivity or remote exploitation. Attackers can leverage this flaw by running a specially crafted application that triggers the vulnerable code path, causing the kernel to execute malicious code with elevated privileges.
The operational impact of CVE-2015-2517 is severe and far-reaching across the affected windows platforms, as it provides attackers with a reliable method for achieving system-level compromise without requiring additional attack vectors. Once successfully exploited, the vulnerability allows attackers to bypass standard security controls including user access control, process isolation, and privilege separation mechanisms that protect against unauthorized system modifications. This elevation of privilege enables malicious actors to install persistent backdoors, modify system files, access encrypted data, and establish long-term access to compromised systems. The vulnerability's impact extends beyond individual system compromise to potential network-wide exploitation, as attackers can use the elevated privileges to move laterally within networks, access sensitive corporate data, and conduct advanced persistent threat operations. From an enterprise security perspective, this vulnerability represents a significant risk to organizations running affected windows versions, as it can be exploited by adversaries with minimal technical skill and no specialized tools beyond basic application development capabilities.
Mitigation strategies for CVE-2015-2517 focus primarily on applying microsoft security patches and implementing additional security controls to reduce exploitation risk. Microsoft released security update kb3045171 as part of their regular patching cycle to address this vulnerability, which should be deployed immediately across all affected systems. Organizations should also implement application whitelisting policies to prevent execution of unauthorized applications that could exploit this vulnerability, particularly in high-risk environments where user access is more permissive. The vulnerability aligns with several attack techniques documented in the mitre att&ck framework under the privilege escalation and persistence domains, specifically targeting techniques that leverage kernel-mode exploits to gain system-level access. Additional defensive measures include monitoring for unusual graphics rendering activity, implementing strict user access controls, and conducting regular security assessments to identify potential exploitation attempts. System administrators should also consider implementing security solutions that can detect and prevent exploitation attempts through behavioral analysis and anomaly detection capabilities. Given the nature of kernel-mode exploits, traditional endpoint protection solutions may not provide adequate defense, making layered security approaches essential for comprehensive protection against this vulnerability.