Null Pointer Dereference in Windows TCP/IP Affects Microsoft Products
CVE-2026-40401

7.1HIGH

Key Information:

Vendor

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

What is CVE-2026-40401?

A null pointer dereference vulnerability has been identified in the TCP/IP stack of Windows operating systems, allowing unauthorized local attackers to trigger a denial of service condition. This can potentially disrupt network operations and affect the availability of services dependent on the TCP/IP stack. It is crucial for users to apply the necessary security updates to mitigate the risk associated with this vulnerability.

Affected Version(s)

Windows 10 Version 1607 x64-based Systems 10.0.14393.0 < 10.0.14393.9140

Windows 10 Version 1809 x64-based Systems 10.0.17763.0 < 10.0.17763.8755

Windows 10 Version 21H2 x64-based Systems 10.0.19044.0 < 10.0.19044.7291

References

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

CVSS V3.1

Score:
7.1
Severity:
HIGH
Confidentiality:
None
Integrity:
None
Availability:
None
Attack Vector:
Local
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Changed

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.