PT-2026-47883 · Microsoft · Windows Tcp/Ip

Published 2026-06-09 · Updated 2026-06-10 · CVE-2026-42904

Positive Technologies (AI Summary)

CVSS v3.1

9.6

Critical

Base vector

AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

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

Description A heap-based buffer overflow in the Windows TCP/IP stack allows an unauthorized attacker located on an adjacent network to elevate privileges to SYSTEM level. A heap-based buffer overflow occurs when a program writes more data to a heap-allocated memory block than it can hold, potentially corrupting adjacent memory.

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

Heap Based Buffer Overflow

Weakness Enumeration

CWE-122

Related Identifiers

CVE-2026-42904

Affected Products

Windows Tcp/Ip

References · 4

• https://nvd.nist.gov/vuln/detail/CVE-2026-42904 · Security Note
• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-42904 · Vendor Advisory
• https://twitter.com/horizon_secured/status/2064406305625047363 · Twitter Post
• https://twitter.com/windowsforum/status/2064530467718561880 · Twitter Post