PT-2026-40219 · Microsoft · Windows Tcp/Ip+1

Published 2026-05-12 · Updated 2026-05-12 · CVE-2026-40406

Positive Technologies (AI Summary)

CVSS v2.0

7.8

High

Base vector

AV:N/AC:L/Au:N/C:C/I:N/A:N

Name of the Vulnerable Software and Affected Versions Windows TCP/IP (affected versions not specified)

Description A use after free issue in Windows TCP/IP allows an unauthorized attacker to disclose sensitive information over a network, which may further affect the system. Use after free is a memory corruption flaw that occurs when an application continues to use a pointer after it has been freed.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Use After Free

Weakness Enumeration

CWE-416

Related Identifiers

BDU:2026-06803

CVE-2026-40406

Affected Products

Windows

Windows Tcp/Ip

References · 5

• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40406 · Vendor Advisory
• https://msrc.microsoft.com/update-guide/en-US/advisory/CVE-2026-40406 · Vendor Advisory
• http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-40406 · Security Note
• https://bdu.fstec.ru/vul/2026-06803 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2026-40406 · Security Note