Cyber Resilience

CVE-2026-42904

CriticalUpdated

Published: 09 June 2026

Published
09 June 2026
Modified
17 June 2026
KEV Added
Patch
CVSS Score v3.1 9.6 CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
EPSS Score 0.0044 35.1th percentile
Risk Priority 70 floored blend · peak EPSS

Summary

CVE-2026-42904 is a critical-severity Heap-based Buffer Overflow (CWE-122) vulnerability in Microsoft Windows 10 21H2. Its CVSS base score is 9.6 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 35.1th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

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

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
Why these techniques?

Heap buffer overflow in Windows TCP/IP stack directly enables local privilege escalation from an adjacent network attacker (T1068).

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

Affected Assets

microsoft
windows 10 21h2
≤ 10.0.19044.7417 · ≤ 10.0.19044.7417 · ≤ 10.0.19044.7417
microsoft
windows 10 22h2
≤ 10.0.19045.7417 · ≤ 10.0.19045.7417 · ≤ 10.0.19045.7417
microsoft
windows 11 23h2
≤ 10.0.22631.7219 · ≤ 10.0.22631.7219
microsoft
windows 11 24h2
≤ 10.0.26100.8655 · ≤ 10.0.26100.8655
microsoft
windows 11 25h2
≤ 10.0.26200.8655 · ≤ 10.0.26200.8655
microsoft
windows 11 26h1
≤ 10.0.28000.2269 · ≤ 10.0.28000.2269
microsoft
windows server 2022
≤ 10.0.20348.5256
microsoft
windows server 2025
≤ 10.0.26100.32995

Mitigating Controls

No mitigating controls mapped yet. The per-CVE control annotator has not reached this CVE.

References