CVE-2026-69374 Windows SMB Server Denial of Service Vulnerability
An authorized attacker can cause a denial of service in Windows SMB Server by exploiting resource allocation limits.
- 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-2026-69374?
CVE-2026-69374 is a medium-severity denial of service vulnerability in Microsoft Windows 10 21h2, published on 8 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Allocation of resources without limits or throttling in Windows SMB Server allows an authorized attacker to deny service over a network.
Weakness: CWE-770
Which versions are affected by CVE-2026-69374?
It affects 8 products.
Products include Microsoft Windows 10 21h2, Microsoft Windows 10 22h2, Microsoft Windows 11 23h2, Microsoft Windows 11 24h2, Microsoft Windows 11 25h2, Microsoft Windows 11 26h1 and 2 more.
How do I fix CVE-2026-69374?
No fix has been published for CVE-2026-69374 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-69374 being exploited?
There is no known exploitation of CVE-2026-69374 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-c3qm-624h-cp2j.