CVE record · CVE-2026-70237

Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability

CVSS 7.0 HighEPSS 0.0032 · 24th percentile

Published by the CVE Program (CNA: microsoft) at 13 Oct 2026, 19:00 UTC. agentprime has not analysed this yet, so whether it affects any app is not known. This CVE names a vendor and product rather than a package, so the lockfile check doesn’t match it.

Affected products, as the CNA wrote them
Vendor	Product	Versions
Microsoft	Windows 10 Version 1607	affected 10.0.14393.0 to before 10.0.14393.9612 custom
Microsoft	Windows 10 Version 1809	affected 10.0.17763.0 to before 10.0.17763.9376 custom
Microsoft	Windows 10 Version 21H2	affected 10.0.19044.0 to before 10.0.19044.7807 custom
Microsoft	Windows 10 Version 22H2	affected 10.0.19045.0 to before 10.0.19045.7807 custom
Microsoft	Windows 11 version 23H2	affected 10.0.22631.0 to before 10.0.22631.7652 custom
Microsoft	Windows 11 Version 23H2	affected 10.0.22631.0 to before 10.0.22631.7652 custom
Microsoft	Windows 11 Version 24H2	affected 10.0.26100.0 to before 10.0.26100.9711 custom
Microsoft	Windows 11 Version 25H2	affected 10.0.26200.0 to before 10.0.26200.9711 custom
Microsoft	Windows 11 version 26H1	affected 10.0.28000.0 to before 10.0.28000.3231 custom
Microsoft	Windows 11 Version 26H2	affected 10.0.26300.0 to before 10.0.26300.9711 custom
Microsoft	Windows Server 2012	affected 6.2.9200.0 to before 6.2.9200.26434 custom
Microsoft	Windows Server 2012 (Server Core installation)	affected 6.2.9200.0 to before 6.2.9200.26434 custom
Microsoft	Windows Server 2012 R2	affected 6.3.9600.0 to before 6.3.9600.23470 custom
Microsoft	Windows Server 2012 R2 (Server Core installation)	affected 6.3.9600.0 to before 6.3.9600.23470 custom
Microsoft	Windows Server 2016	affected 10.0.14393.0 to before 10.0.14393.9612 custom
Microsoft	Windows Server 2016 (Server Core installation)	affected 10.0.14393.0 to before 10.0.14393.9612 custom
Microsoft	Windows Server 2019	affected 10.0.17763.0 to before 10.0.17763.9376 custom
Microsoft	Windows Server 2019 (Server Core installation)	affected 10.0.17763.0 to before 10.0.17763.9376 custom
Microsoft	Windows Server 2022	affected 10.0.20348.0 to before 10.0.20348.5761 custom
Microsoft	Windows Server 2025	affected 10.0.26100.0 to before 10.0.26100.33650 custom
Microsoft	Windows Server 2025 (Server Core installation)	affected 10.0.26100.0 to before 10.0.26100.33650 custom

Identifiers: CVE-2026-70237
CNA: microsoft
Weakness (CWE): CWE-416
Tags: Microsoft Windows 10 Version 1607
Microsoft Windows 10 Version 1809
Microsoft Windows 10 Version 21H2
Microsoft Windows 10 Version 22H2
Microsoft Windows 11 version 23H2
Microsoft Windows 11 Version 24H2
Microsoft Windows 11 Version 25H2
Microsoft Windows 11 version 26H1
Memory corruption
Published: 13 Oct 2026
Updated: 31 Oct 2026

Not analysed yet

We haven’t published our own analysis of this CVE. If a person reviews it, this page will say what’s affected and what has to be true for it to matter.

Severity and exploitation

Score	Rating	CVSS	Vector	Source
7.0	High	3.1	CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C	CNA (microsoft)

CISA KEV Not listed.
EPSS 0.0032, the 24th percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

13 Oct 2026, 19:00 UTC Confirmed by the CVE List
31 Oct 2026, 16:26 UTC First seen by agentprime

Sources

References from the CNA

msrc.microsoft.com/update-guide/vulnerability/CVE-2026-70237 vendor-advisorypatch

Facts on this page come from the CVE List as the CNA published them, with CVSS from the sources named above, CISA KEV and FIRST EPSS. Vendors, products and versions are shown as the CNA wrote them. We don’t reproduce the CVE’s description.