Heap-Based Buffer Overflow in Windows Hyper-V by Microsoft
CVE-2026-21248

7.3HIGH

Key Information:

Vendor

Microsoft
Status
Windows 10 Version 1607
Windows 10 Version 1809
Windows 10 Version 21h2
Windows 10 Version 22h2
Vendor
CVE Published:
10 February 2026

What is CVE-2026-21248?

A heap-based buffer overflow vulnerability exists in Windows Hyper-V, which could allow an authorized attacker to execute arbitrary code locally. This flaw can be exploited by an attacker with sufficient privileges on the affected system, leading to potential unauthorized access and manipulation of system operations. It is essential for users to apply the available patches to safeguard their systems from this risk.

Affected Version(s)

Windows 10 Version 1607 x64-based Systems 10.0.14393.0 < 10.0.14393.8868

Windows 10 Version 1809 x64-based Systems 10.0.17763.0 < 10.0.17763.8389

Windows 10 Version 21H2 x64-based Systems 10.0.19044.0 < 10.0.19044.6937

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE...
vendor-advisorypatch

CVSS V3.1

Score:
7.3
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Local
Attack Complexity:
Low
Privileges Required:
Low
User Interaction:
Required
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

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