CVE-2026-68820
Microsoft Windows Ancillary Function Driver for WinSock Use-After-Free Vulnerability
This vulnerability is in the CISA Known Exploited Vulnerabilities catalog: attackers are using it. If you run Windows Ancillary Function Driver for WinSock, fix it now.
CISA required action: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
US federal civilian agencies must remediate by Aug 25, 2026.
Patch status
Official fix available since
Apply the vendor's update to every affected system. Check the fixed-in versions below where known.
Basis: NVD patch reference
Description
Use after free in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.
Source: NIST National Vulnerability Database. Official vulnerability data, reproduced as published.
Affected products
| Product | Vendor | Source |
|---|---|---|
| Windows Ancillary Function Driver for WinSock | Microsoft | KEV |
Sources: KEV = CISA Known Exploited Vulnerabilities catalog. Version details have not been published yet.
Intelligence timeline
Developments from the last 30 days, newest first.
No developments recorded for CVE-2026-68820 in the last 30 days.
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Coverage
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