CVE-2026-83636 Null pointer dereference in Windows Hyper-V allows an authorized attacker to deny service locally

Description

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

Affected products and versions

Product	Affected versions	Fixed in
Windows 10 Version 21H2 10.0	10.0.19044.0 → < 10.0.19044.7807	10.0.19044.7807
Windows 10 Version 22H2 10.0	10.0.19045.0 → < 10.0.19045.7807	10.0.19045.7807
Windows 11 Version 23H2 10.0	10.0.22631.0 → < 10.0.22631.7652	10.0.22631.7652
Windows 11 Version 24H2 10.0	10.0.26100.0 → < 10.0.26100.9711	10.0.26100.9711
Windows 11 Version 25H2 10.0	10.0.26200.0 → < 10.0.26200.9711	10.0.26200.9711
Windows 11 version 26H1 10.0	10.0.28000.0 → < 10.0.28000.3231	10.0.28000.3231
Windows 11 Version 26H2 10.0	10.0.26300.0 → < 10.0.26300.9711	10.0.26300.9711
Windows Server 2022 10.0	10.0.20348.0 → < 10.0.20348.5761	10.0.20348.5761
Windows Server 2025 10.0	10.0.26100.0 → < 10.0.26100.33650	10.0.26100.33650

Show the other branch Hide the other branch

Product	Affected versions	Fixed in
Windows Server 2025 (Server Core installation) 10.0	10.0.26100.0 → < 10.0.26100.33650	10.0.26100.33650

Other CVEs of Windows 10 Version 21H2

The 4539 CVEs of Windows 10 Version 21H2 →

CVE-2026-108135 Improper link resolution before file access ('link following') in Windows Backup Engine allows an authorized attacker to… 7.0 High CVE-2026-108136 Use after free in Microsoft Windows Search Component allows an authorized attacker to elevate privileges locally 7.8 High CVE-2026-108131 No cwe for this issue in Active Directory Federation Services (AD FS) allows an unauthorized attacker to perform… 7.5 High CVE-2026-108129 Out-of-bounds read in DNS Server allows an authorized attacker to disclose information over a network 6.5 Medium