CVE-2015-1727 in Windows
Summary
by MITRE
Buffer overflow in the kernel-mode drivers in Microsoft Windows Server 2003 SP2 and R2 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, aka "Win32k Pool Buffer Overflow Vulnerability."
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Analysis
by VulDB Data Team • 07/07/2025
The CVE-2015-1727 vulnerability represents a critical buffer overflow flaw within the kernel-mode drivers of multiple Microsoft Windows operating systems including Windows Server 2003 SP2 and R2 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. This vulnerability specifically affects the win32k.sys driver which manages user-mode graphics components and handles windowing operations within the Windows kernel. The flaw stems from improper validation of input data within the kernel-mode driver, creating a condition where maliciously crafted data can overwrite adjacent memory locations in the kernel pool. This type of vulnerability falls under CWE-121, which describes stack-based buffer overflow conditions, though the specific implementation involves heap-based memory corruption in kernel space. The vulnerability is particularly dangerous because it operates within the kernel context, providing a direct pathway for privilege escalation attacks.
The technical exploitation of this vulnerability requires a local attacker to execute a specially crafted application that triggers the vulnerable code path within the win32k.sys driver. When the driver processes malformed input data, the buffer overflow occurs in the kernel pool memory allocation, allowing the attacker to overwrite critical kernel data structures or execute arbitrary code with kernel-level privileges. This mechanism enables attackers to bypass standard security boundaries and elevate their privileges from user-level to system-level access. The vulnerability demonstrates characteristics consistent with the ATT&CK technique T1068, which involves exploiting legitimate credentials and privileges to gain system-level access. The flaw affects the graphics subsystem's handling of window objects and GDI (Graphics Device Interface) operations, making it particularly insidious as it can be triggered through normal user interaction with graphical applications.
The operational impact of CVE-2015-1727 is severe and far-reaching across enterprise environments, as it provides local attackers with a straightforward path to system compromise and privilege escalation. Organizations running affected Windows versions face significant risk of unauthorized system access, data exfiltration, and persistent backdoor establishment. The vulnerability's presence in both server and client operating systems means that it can be exploited across various deployment scenarios, from desktop workstations to critical server infrastructure. Attackers can leverage this vulnerability to establish persistent access, deploy additional malware, or conduct lateral movement within networks. The exploitability factor is high since it requires only local execution privileges and does not depend on network connectivity or external attack vectors, making it particularly dangerous in insider threat scenarios or compromised user accounts. This vulnerability directly impacts the integrity and confidentiality of systems by allowing unauthorized access to kernel memory and critical system resources.
Mitigation strategies for CVE-2015-1727 primarily involve applying Microsoft's security patches and updates as soon as they become available, with the vulnerability being addressed through the Microsoft Security Update KB3038240 and related patches. Organizations should implement comprehensive patch management processes to ensure timely deployment of security updates across all affected systems. Additional defensive measures include implementing application whitelisting policies, disabling unnecessary graphical features, and monitoring for suspicious kernel-mode activity through endpoint detection and response solutions. Network segmentation and privilege separation can help limit the potential impact of successful exploitation attempts. System administrators should also consider implementing security configurations that reduce the attack surface, such as disabling unnecessary services and restricting local user privileges. The vulnerability's classification as a kernel-mode buffer overflow makes it particularly resistant to traditional antivirus solutions, emphasizing the importance of proactive patching and system hardening measures. Organizations should also conduct regular vulnerability assessments and penetration testing to identify and remediate similar vulnerabilities within their Windows environments.