CVE-2026-50462 in Windows
Summary
by MITRE • 07/14/2026
External control of file name or path in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.
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Analysis
by VulDB Data Team • 07/14/2026
This vulnerability represents a critical privilege escalation flaw in the Windows Ancillary Function Driver for WinSock component that enables authenticated attackers to manipulate file paths and potentially execute arbitrary code with elevated privileges. The issue stems from insufficient validation of user-supplied input within the driver's handling of file names and paths, creating an attack surface where malicious actors can craft specific inputs to exploit the vulnerable code path. Such vulnerabilities typically fall under CWE-73 which specifically addresses external control of filename or path, a well-documented weakness that has been consistently exploited in various Windows components over time.
The technical implementation of this vulnerability involves the ancillary function driver's failure to properly sanitize or validate file path inputs received from user-mode applications. When legitimate processes interact with the WinSock functionality, the driver may accept unvalidated path specifications that could be manipulated to reference system-critical files or directories. This flaw allows an attacker to potentially redirect file operations to arbitrary locations, enabling them to overwrite system binaries, modify security-critical files, or create malicious executables in privileged locations. The vulnerability is particularly dangerous because it operates at the kernel level within the Windows networking stack, providing attackers with direct access to system resources that would normally be protected from user-space manipulation.
Operationally, this vulnerability presents a significant risk for local privilege escalation attacks where an authenticated user with minimal privileges can elevate their access level to SYSTEM or administrator rights. Attackers typically exploit such flaws by crafting malicious file operations that leverage the driver's path handling weaknesses to gain code execution in kernel mode contexts. The attack vector often involves creating specific file path manipulations that cause the driver to perform operations on unexpected targets, potentially leading to complete system compromise. This type of vulnerability aligns with ATT&CK technique T1068 which covers local privilege escalation through kernel exploits and driver manipulation.
Security mitigations for this vulnerability should include comprehensive input validation within the driver code to prevent untrusted path inputs from being processed without proper sanitization. Microsoft typically addresses such issues through security updates that implement stricter path validation, enhance kernel-mode input handling, and improve the overall robustness of driver interfaces. Organizations should maintain up-to-date systems with the latest Windows patches and consider implementing additional controls such as kernel mode code integrity checks, restricted file system access permissions, and monitoring for anomalous file operations within the affected driver components. The vulnerability demonstrates the importance of secure coding practices in kernel-mode drivers and highlights how seemingly simple input validation issues can result in severe privilege escalation capabilities that threaten entire system security models.