HIGH
CVE-2026-40401
CWE-476Published: May 12, 2026· Updated: May 15, 2026
7.1
CVSS v3.1
EPSS:0.05%probability of exploitation in 30 daysPercentile:16.1th
Official Description
Null pointer dereference in Windows TCP/IP allows an unauthorized attacker to deny service locally.
Technical Analysis
CVE-2026-40401 requires local access, meaning attackers must already have a foothold on the target system.
The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.
A successful exploit results in availability disruption (denial of service), with a CVSS base score of 7.1.
The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.
CVSS v3.1 Vector Breakdown
Exploitability
Attack VectorLocal
Attack ComplexityLow
Privileges Req.None
User InteractionNone
ScopeChanged
Impact
ConfidentialityNone
IntegrityNone
AvailabilityHigh
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Affected Vendors & Products
Microsoft14 products
windows 10 1607windows 10 1809windows 10 21h2windows 10 22h2windows 11 23h2windows 11 24h2windows 11 25h2windows 11 26h1windows server 2012windows server 2016windows server 2019windows server 2022+2 more
Source: NVD CPE · 15 total CPE entries
Exploit & PoC Resources
NO KNOWN EXPLOITNo public exploit confirmed at this time
Exploit-DB
Offensive Security exploit database
GitHub PoC Search
Community PoC repositories
Rapid7 / Metasploit
Metasploit module search
PacketStorm
Security advisories & exploits
NVD Detail
Official NIST entry
MITRE CVE
CVE Program entry
External links open in a new tab. Always verify in a controlled environment before use.
Official Patches & Advisories
All References (1)
Quick Facts
CVE IDCVE-2026-40401
CVSS Score7.1 / 10
SeverityHIGH
WeaknessCWE-476
CISA KEVNo
EPSS (30d)0.05%
Affected1 vendor
PublishedMay 12, 2026
Related CVEs (CWE-476)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2026-40401 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.