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CVE-2025-49661

afd.sys — untrusted pointer dereference allows elevation of privilege

Summary

Field Value
Driver afd.sys
Vulnerability Class Untrusted Pointer Dereference
CVSS 7.8
Exploited ITW No
Patch Date July 8, 2025

Root Cause

The AFD driver dereferences a user-supplied pointer in a kernel-mode code path without validating it. A local attacker gets a controlled pointer dereference primitive that corrupts kernel memory.

Exploitation

The attacker passes a crafted pointer through a WinSock operation. The kernel dereferences the untrusted pointer, giving a write or read primitive depending on the code path. Chaining with heap spraying yields SYSTEM.

Exploitation Primitive

Crafted WinSock operation → untrusted pointer dereference
  → kernel memory corruption → SYSTEM

References