Main Vulnerability Database Vulnerabilities #VU131277

Use-after-free in Windows and Windows Server - CVE-2026-40406

Published: May 12, 2026

Vulnerability identifier: #VU131277

CSH Severity: Medium

CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green

CVE-ID: CVE-2026-40406

CWE-ID: CWE-416

Exploitation vector: Remote access

Exploit availability: No public exploit available

Vendor: Microsoft

Affected software:
Windows
Windows Server

Detailed vulnerability description

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a use-after-free error in Windows TCP/IP. A remote attacker can gain access to sensitive information on the system.

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