CVE intelligenceCISA KEV

CVE-2026-68820

Microsoft Windows Ancillary Function Driver for WinSock Use-After-Free Vulnerability

Published Aug 11, 2026Sources checked Oct 28, 2026

7.0HIGHCVSS out of 10

What this means

Actively exploited

CISA lists CVE-2026-68820 in its Known Exploited Vulnerabilities catalog, which means exploitation has been observed. The entry applies to Microsoft Windows Ancillary Function Driver for WinSock.

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.

Public exploit: Not collected.

Microsoft Security Response Center: Exploitation reported by Microsoft Security Response Center (2026-08-11)
Microsoft exploitation status: Exploited:Yes

What to do next

Remediation and response

Review the linked vendor advisory and apply the mitigation or fixed release for your affected product.

Microsoft Security Response Center guidance

Vendor revision: Aug 11, 2026

Vendor remediation details

Install KB5120238. Install KB5120242. Install KB5120229. Install KB5120249. Install KB5120233. Install KB5120228. Install KB5121003. Install KB5120994. Install KB5120240. Install KB5121000. Install KB5120418. Install KB5120386. Install KB5120385.

Vendor-listed releases

10.0.17763.9121
10.0.20348.5499
10.0.20348.5440
10.0.19044.7663
10.0.19045.7663
10.0.26100.33296
10.0.26100.33222
10.0.26200.9168
10.0.26200.9106
10.0.22631.7517
10.0.26100.9168
10.0.26100.9106
10.0.28000.2704
10.0.14393.9418
6.2.9200.26280
6.3.9600.23338

CISA KEVListedObserved exploitation

EPSS0.3%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors1Source-linked actor relationships

Overview

What is CVE-2026-68820?

Use after free in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.

Source: NVD

Reported activity: Microsoft exploitation status: Exploited:Yes
Microsoft Security Response Center · Published Aug 11, 2026

CISA says: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.CISA catalog due date Aug 25, 2026