CVE-2026-68820

Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability

HIGH

CVSS Score

Published: August 11, 2026 at 05:05 PM UTC

Updated: October 28, 2026 at 08:06 PM UTC

13 products affected across 1 vendorWindows Server 2016Windows Server 2019Windows Server 2012

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Severity

HIGH7

Exploitation

CISA KEV

Exploit prediction

EPSS 0.3%

SSVC

Active

Actively Exploited

CISA Known Exploited Vulnerabilities (KEV) Catalog

EPSS Score0.3%

EPSS (Exploit Prediction Scoring System) estimates a 0.3% chance this CVE is exploited in the wild within the next 30 days — higher than 26% of all CVEs. It complements CVSS: a high EPSS on a mid-severity CVE can still be urgent.

Microsoft Windows Ancillary Function Driver for WinSock contains a use-after-free vulnerability that allows an authorized attacker to elevate privileges locally.

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.

Ransomware Use

Unknown

Added to KEV

Aug 11, 2026

Remediation Due

Aug 25, 2026

66 days overdue

Notes

https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2026-68820

BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk

Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk

https://nvd.nist.gov/vuln/detail/CVE-2026-68820

Description

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

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Windows 10 1607 · Microsoft

95%

v < 10.0.14393.941810.0.14393.0

Affected range stops below 10.0.14393.9418, so it looks safe — our inference, not a vendor statement

Windows 10 1809 · Microsoft

95%

v < 10.0.17763.911510.0.17763.0

Affected range stops below 10.0.17763.9115, so it looks safe — our inference, not a vendor statement

Affected range stops below 10.0.17763.9121, so it looks safe — our inference, not a vendor statement

Windows 10 21H2 · Microsoft

95%

v < 10.0.19044.766310.0.19044.0

Affected range stops below 10.0.19044.7663, so it looks safe — our inference, not a vendor statement

Windows 10 22H2 · Microsoft

95%

v < 10.0.19045.766310.0.19045.0

Affected range stops below 10.0.19045.7663, so it looks safe — our inference, not a vendor statement

Windows 11 23H2 · Microsoft

95%

v < 10.0.22631.751710.0.22631.0

Affected range stops below 10.0.22631.7517, so it looks safe — our inference, not a vendor statement

Windows 11 24H2 · Microsoft

95%

v < 10.0.26100.910610.0.26100.0

Affected range stops below 10.0.26100.9106, so it looks safe — our inference, not a vendor statement

Affected range stops below 10.0.26100.9168, so it looks safe — our inference, not a vendor statement

Windows 11 25H2 · Microsoft

95%

v < 10.0.26200.910610.0.26200.0

Affected range stops below 10.0.26200.9106, so it looks safe — our inference, not a vendor statement

Affected range stops below 10.0.26200.9168, so it looks safe — our inference, not a vendor statement

Windows 11 26H1 · Microsoft

95%

v < 10.0.28000.270410.0.28000.0

Affected range stops below 10.0.28000.2704, so it looks safe — our inference, not a vendor statement

Windows Server 2012 · Microsoft

95%

6.2.9200.0 6.3.9600.0 r2

Affected range stops below 6.2.9200.26280, so it looks safe — our inference, not a vendor statement

Affected range stops below 6.3.9600.23338, so it looks safe — our inference, not a vendor statement

Windows Server 2016 · Microsoft

95%

v < 10.0.14393.941810.0.14393.0

Affected range stops below 10.0.14393.9418, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-68820

References (2)

Vendor AdvisoryPatch

Source: cverecord

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-68820

US Government Resource

Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0

https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-68820

SSVC — Action Prioritization

SSVCActiveNot automatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7HIGHmicrosoft

Vector?

Quick Info

StatusANALYZED

CWE

CWE-416

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