CVE-2026-40405
Windows TCP/IP Denial of Service vulnerability
MSRC advisory May 12, 2026
Alert details
- Source feed
- Microsoft MSRC
- CVE ID
- CVE-2026-40405
- Affected products
- Windows TCP/IP Denial of Service · Microsoft Windows TCP/IP Denial of Service · Microsoft
What happened
Null pointer dereference in Windows TCP/IP allows an unauthorized attacker to deny service over a network.
What it means for your business
Windows TCP/IP Denial of Service vulnerability (CVE-2026-40405) was added to Microsoft’s security update guidance. Null pointer dereference in Windows TCP/IP allows an unauthorized attacker to deny service over a network. PremierePC tracks MSRC advisories for Upstate SC businesses — patch or open a ticket if you need help verifying exposure.
EPSS probability
1.08%
Sources
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Need help patching?
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