CVE-2026-56168: Microsoft Windows SMB Server null pointer dereference

CVE-2026-56168 · Severity: medium · CVSS 6.5 · Published 2026-07-14

A vulnerability in the Windows Server Message Block (SMB) service could allow an authorized user to crash the system remotely. SMB is a standard protocol used by Windows for sharing files and printers across a network. While this flaw does not allow for data theft, it can be used to disrupt business operations by causing a denial-of-service state on affected servers and workstations.

Technologies: Microsoft Windows 11, Microsoft Windows 10, Microsoft Windows Server 2022, Microsoft Windows Server 2025. Vendors: Microsoft.

Quick answers

Is CVE-2026-56168 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-56168 being exploited in the wild.
How severe is CVE-2026-56168?
Medium severity, with a CVSS score of 6.5, published 14 July 2026.
Which products and versions are affected?
Microsoft Windows 11 10.0.26100.0 to 10.0.26100.8875; Microsoft Windows 10 10.0.19044.0 to 10.0.19044.7548; Microsoft Windows Server 2022 10.0.20348.0 to 10.0.20348.5386; Microsoft Windows Server 2025 10.0.26100.0 to 10.0.26100.33158.
Is there a fix for CVE-2026-56168?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-56168 attacked?
It is attacked over the network, in an operating system.
Am I affected by CVE-2026-56168?
Check whether you run Microsoft Windows 11, Microsoft Windows 10, Microsoft Windows Server 2022 or one of the others listed at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A NULL pointer dereference vulnerability (CWE-476) exists in the Microsoft Windows SMB Server component. An attacker with low-privileged network access can exploit this flaw by sending specially crafted requests to the SMB service. Successful exploitation results in a denial-of-service (DoS) condition, typically manifesting as a system crash or service interruption. The vulnerability affects multiple versions of Windows 10, Windows 11, and Windows Server. Microsoft has released security updates to address this issue.

Affected products

  • Microsoft Windows 10 Version 21H2 10.0.19044.0 to 10.0.19044.7548
  • Microsoft Windows 10 Version 22H2 10.0.19045.0 to 10.0.19045.7548
  • Microsoft Windows 11 Version 24H2 10.0.26100.0 to 10.0.26100.8875
  • Microsoft Windows 11 Version 25H2 10.0.26200.0 to 10.0.26200.8875
  • Microsoft Windows 11 version 26H1 10.0.28000.0 to 10.0.28000.2269
  • Microsoft Windows Server 2022 10.0.20348.0 to 10.0.20348.5386
  • Microsoft Windows Server 2025 10.0.26100.0 to 10.0.26100.33158

Timeline

  • 2026-07-14: advisory: Initial publication by Microsoft and NVD

References

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