CVE-2026-40405
Windows TCP/IP Denial of Service Vulnerability
Null pointer dereference in Windows TCP/IP allows an unauthorized attacker to deny service over a network.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
Windows TCP/IP Denial of Service Vulnerability
Null pointer dereference in Windows TCP/IP allows an unauthorized attacker to deny service over a network.
- Record
CVE-2026-40405- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C - Weakness
- CWE-476
- Updated
- 2026-11-02
EUVDEUVD-2026-29665
Null pointer dereference in Windows TCP/IP allows an unauthorized attacker to deny service over a network.
- Record
EUVD-2026-29665- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-mj3g-9j9x-c556
Null pointer dereference in Windows TCP/IP allows an unauthorized attacker to deny service over a...
Null pointer dereference in Windows TCP/IP allows an unauthorized attacker to deny service over a network.
- Record
GHSA-mj3g-9j9x-c556- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-476
- Updated
- 2026-11-02
NVD
Null pointer dereference in Windows TCP/IP allows an unauthorized attacker to deny service over a network.
- Record
CVE-2026-40405- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-476
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-40405 is a high vulnerability (CVSS 7.5) in Microsoft Windows 11 Version 24h2, published May 12, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.08%, the 65th percentile. No source names a fixed version.