Microsoft Windows Ancillary Function Driver for WinSock Privilege Escalation Vulnerability

A vulnerability in the Windows Ancillary Function Driver for WinSock allows an authorized attacker to gain elevated privileges locally. This issue arises from external control of file names or paths, which could be exploited to manipulate file handling in a way that increases the attacker's privileges.

Impact

Exploitation of this vulnerability could lead to unauthorized privilege escalation, allowing a user to gain higher-level access or permissions than intended.

Remediation

Users can apply the security update for this vulnerability, which is included in the July 2026 Monthly Rollup, available through the Microsoft Update Catalog. Specific update details can be found in the Microsoft Knowledge Base articles KB5099444, KB5099445, KB5099535, KB5101649, KB5099536, KB5099540, and KB5099538.