CVE-2026-56168 Windows SMB Server Denial of Service Vulnerability
An authorized attacker can cause a denial of service in Windows SMB Server via a null pointer dereference.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-56168?
CVE-2026-56168 is a medium-severity vulnerability in Microsoft Windows 10 21h2, published on 14 Jul 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Null pointer dereference in Windows SMB Server allows an authorized attacker to deny service over a network.
Weakness: CWE-476
Which versions are affected by CVE-2026-56168?
It affects 7 products.
Products include Microsoft Windows 10 21h2, Microsoft Windows 10 22h2, Microsoft Windows 11 24h2, Microsoft Windows 11 25h2, Microsoft Windows 11 26h1, Microsoft Windows Server 2022 and 1 more.
How do I fix CVE-2026-56168?
No fix has been published for CVE-2026-56168 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-56168 being exploited?
There is no known exploitation of CVE-2026-56168 in the wild and no public exploit code.
Other vulnerabilities in Microsoft Windows 10 21h2
- CVE-2025-21333 Microsoft Windows Hyper-V NT Kernel Integration VSP Heap-based Buffer Overflow
- CVE-2025-21334 Microsoft Windows Hyper-V NT Kernel Integration VSP Use-After-Free
- CVE-2025-21335 Microsoft Windows Hyper-V NT Kernel Integration VSP Use-After-Free
- CVE-2026-42904 Windows TCP/IP Elevation of Privilege Vulnerability
- CVE-2026-105733 Windows Hyper-V Remote Code Execution Vulnerability
Sources
Also known as GHSA-2875-28w4-4vqx.