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CVE-2026-83636

Windows Hyper-V Denial of Service Vulnerability

Microsoft Windows 10 Version 21H2Operating systems
Open in ThreatlineRecord JSON
CVSS
6.5Medium
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.39%Chance of exploitation activity in the next 30 days, higher than 32% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed in10.0.19044.7807Also 10.0.19045.7807, 10.0.22631.7652 and 6 moreCVE List
Published13 Oct 2026Updated 23 Oct 2026CVE List

What fixes it

  • 10.0.19044.7807Windows 10 Version 21H2CVE List
  • 10.0.19045.7807Windows 10 Version 22H2CVE List
  • 10.0.22631.7652Windows 11 version 23H2CVE List
  • 10.0.22631.7652Windows 11 Version 23H2CVE List
  • 10.0.26100.9711Windows 11 Version 24H2CVE List
  • 10.0.26200.9711Windows 11 Version 25H2CVE List
Show all 11 fixed versions
  • 10.0.28000.3231Windows 11 version 26H1CVE List
  • 10.0.26300.9711Windows 11 Version 26H2CVE List
  • 10.0.20348.5761Windows Server 2022CVE List
  • 10.0.26100.33650Windows Server 2025CVE List
  • 10.0.26100.33650Windows Server 2025 (Server Core installation)CVE List

A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.

Vendor and government advisories 1

Vendors that say their products are affected, and agencies that issued alerts. Check each for the fixed release of the product you run.

Reports 1

1 outlet mention it. Reports are not confirmation; each links to its source.

Description

Null pointer dereference in Windows Hyper-V allows an authorized attacker to deny service locally.

Text from CVE List

Affected versions 11

  • Windows 10 Version 21H2affected: 10.0.19044.0 before 10.0.19044.7807CVE List
  • Windows 10 Version 22H2affected: 10.0.19045.0 before 10.0.19045.7807CVE List
  • Windows 11 version 23H2affected: 10.0.22631.0 before 10.0.22631.7652CVE List
  • Windows 11 Version 23H2affected: 10.0.22631.0 before 10.0.22631.7652CVE List
  • Windows 11 Version 24H2affected: 10.0.26100.0 before 10.0.26100.9711CVE List
  • Windows 11 Version 25H2affected: 10.0.26200.0 before 10.0.26200.9711CVE List
  • Windows 11 version 26H1affected: 10.0.28000.0 before 10.0.28000.3231CVE List
  • Windows 11 Version 26H2affected: 10.0.26300.0 before 10.0.26300.9711CVE List
  • Windows Server 2022affected: 10.0.20348.0 before 10.0.20348.5761CVE List
  • Windows Server 2025affected: 10.0.26100.0 before 10.0.26100.33650CVE List
  • Windows Server 2025 (Server Core installation)affected: 10.0.26100.0 before 10.0.26100.33650CVE List

References 1