Windows Ancillary Function Driver WinSock UAF EoP

Local privilege escalation in the Windows Ancillary Function Driver for WinSock (AFD.sys) allows an authenticated low-privileged user to elevate to SYSTEM by triggering a use-after-free condition in the kernel-mode driver. No public exploit identified at time of analysis and the issue is not listed in CISA KEV, but AFD.sys has a long history of being targeted for kernel EoP, making this a likely candidate for future weaponization. CVSS 7.0 reflects the high attack complexity required to reliably win the underlying race or reuse condition.

Local privilege escalation in the Windows Ancillary Function Driver for WinSock (afd.sys) allows an authenticated low-privileged user to elevate to SYSTEM via a use-after-free condition. The flaw affects Microsoft Windows installations using the standard WinSock kernel driver and has a vendor-released patch available through Microsoft's security update guide. No public exploit has been identified at time of analysis, though afd.sys has historically been a frequent target for elevation-of-privilege exploitation.