CVE-2025-58714 Overview
CVE-2025-58714 is an improper access control vulnerability in the Windows Ancillary Function Driver for WinSock (afd.sys). An authenticated local attacker can abuse the flaw to elevate privileges on affected Windows systems. Microsoft addressed the issue in its October 2025 security update cycle. The weakness is tracked under CWE-284: Improper Access Control and affects a broad range of Windows client and server releases, including current Windows 11 and Windows Server 2025 builds. Successful exploitation grants code execution in the context of higher-privileged accounts, typically SYSTEM.
Critical Impact
Local attackers with a standard user account can elevate to SYSTEM by exploiting improper access control in the WinSock kernel driver, enabling full compromise of the affected host.
Affected Products
- Microsoft Windows 10 (1507, 1607, 1809, 21H2, 22H2)
- Microsoft Windows 11 (22H2, 23H2, 24H2, 25H2)
- Microsoft Windows Server 2008, 2012, 2016, 2019, 2022, 2022 23H2, and 2025
Discovery Timeline
- 2025-10-14 - CVE-2025-58714 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-58714
Vulnerability Analysis
The Ancillary Function Driver for WinSock, implemented as afd.sys, is a kernel-mode driver that exposes the transport interface used by the Windows Sockets API. User-mode processes interact with afd.sys through \Device\Afd handles and I/O control (IOCTL) requests. The driver mediates socket operations, buffer management, and asynchronous I/O between user mode and the TCP/IP stack.
CVE-2025-58714 arises from improper access control within this driver. An authorized local user can issue crafted requests that the driver processes without adequately verifying the caller's privileges or the target object's protections. The result is a privilege boundary violation between a low-privileged user session and kernel context.
Root Cause
The root cause is a missing or insufficient access check on a code path reachable from user mode, classified as [CWE-284]. The driver acts on requests that should be restricted to higher-privileged callers or protected objects, allowing an attacker to manipulate state that leads to arbitrary code execution in kernel context.
Attack Vector
Exploitation requires local access and valid credentials on the target system. An attacker running as a standard user opens a handle to the AFD device, issues the vulnerable request sequence, and leverages the resulting access control gap to obtain SYSTEM privileges. No user interaction is needed beyond executing the exploit. Microsoft has not reported in-the-wild exploitation, and no public proof-of-concept is currently listed.
No verified public exploit code is available. Refer to the Microsoft Security Update for CVE-2025-58714 for authoritative technical guidance.
Detection Methods for CVE-2025-58714
Indicators of Compromise
- Unexpected user-mode processes opening handles to \Device\Afd followed by token manipulation or spawning of SYSTEM-level child processes.
- New services, scheduled tasks, or persistence artifacts created by processes that recently transitioned from a standard user to SYSTEM context.
- Unsigned or unusual binaries writing to protected directories such as C:\Windows\System32 shortly after suspicious socket activity.
Detection Strategies
- Monitor for standard user processes that acquire SYSTEM tokens without an accompanying legitimate service invocation.
- Alert on abnormal IOCTL patterns to afd.sys originating from non-network applications.
- Correlate process integrity level changes with parent-child process anomalies in EDR telemetry.
Monitoring Recommendations
- Ingest Sysmon Event ID 1 (process creation) and Event ID 10 (process access) into your SIEM and baseline expected callers of AFD.
- Enable Windows kernel-mode audit logging and forward events to a centralized data lake for retention and hunting.
- Track patch compliance for the October 2025 cumulative update across all Windows endpoints and servers.
How to Mitigate CVE-2025-58714
Immediate Actions Required
- Apply the October 2025 Microsoft security update to every affected Windows client and server as soon as testing allows.
- Prioritize patching on multi-user systems, terminal servers, and jump hosts where local privilege escalation has the highest blast radius.
- Audit local account membership and remove unnecessary interactive logon rights to reduce the pool of potential attackers.
Patch Information
Microsoft released fixes as part of the October 14, 2025 security update cycle. Refer to the Microsoft Security Update Guide for CVE-2025-58714 for the specific KB numbers corresponding to each affected Windows version, and deploy through Windows Update, WSUS, Microsoft Intune, or your standard patch management pipeline.
Workarounds
- No official workaround is published by Microsoft; patching is the only sanctioned remediation.
- Restrict local logon rights and enforce least privilege to limit which accounts can attempt local exploitation.
- Enable attack surface reduction rules and application control policies to constrain execution of unauthorized binaries used to trigger the flaw.
# Verify installed updates on a Windows host (PowerShell)
Get-HotFix | Sort-Object -Property InstalledOn -Descending | Select-Object -First 10
# Query Windows Update history for the October 2025 rollup
wmic qfe list brief /format:table
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
