CVE-2026-42904

CRITICAL

Heap-based buffer overflow in Windows TCP/IP allows an unauthorized attacker to elevate privileges over an adjacent network.

CVSS v3.1 Score

9.6
CRITICAL
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
Attack Vector
ADJACENT_NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Published: 6/9/2026Modified: 6/11/2026

Related Intelligence (2)

CRITICALZero Day

Patch Tuesday - June 2026

Microsoft is publishing 200 vulnerabilities on June 2026 Patch Tuesday . Microsoft is not aware of exploitation in the wild for any of these vulnerabilities, and is aware of public disclosure for three. This is similar to last month’s Patch Tuesday, however several of last month’s vulnerabilities ended up on CISA KEV in the days following their publication. So far this month, Microsoft has provide

CVE-2026-33825CVE-2026-45585
Rapid7
CRITICALVulnerability

NVD CRITICAL: CVE-2026-42904 — Heap-based buffer overflow in Windows TCP/IP allows an unauthorized attacker to ...

Heap-based buffer overflow in Windows TCP/IP allows an unauthorized attacker to elevate privileges over an adjacent network.

CVE-2026-42904
NIST NVD

References (1)

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-42904Vendor Advisory