What is CVE-2026-40399?

CVE-2026-40399 is a security advisory published by Microsoft Security Response Center (MSRC) with Elevation of Privilege severity. Windows TCP/IP Elevation of Privilege Vulnerability

Which CVE IDs does CVE-2026-40399 cover?

CVE-2026-40399 covers the following CVE IDs: CVE-2026-40399. Each CVE has its own detail page on EchelonGraph Pulse with the synthesized EG score.

What is the CVSS v3 score of CVE-2026-40399?

CVE-2026-40399 has a CVSS v3 base score of 7.8, published by Microsoft Security Response Center (MSRC).

CVE-2026-40399Elevation of PrivilegeCVSS 7.8

Windows TCP/IP Elevation of Privilege Vulnerability

Vendor

Microsoft Security Response Center (MSRC)

Published

May 22, 2026

Last Modified

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🔗 CVE IDs covered (1)

CVE-2026-40399 →

📋 Description

<p>Stack-based buffer overflow in Windows TCP/IP allows an authorized attacker to elevate privileges locally.</p>