Cyber Resilience

CVE-2026-45657

CriticalUpdated

Published: 09 June 2026

Published
09 June 2026
Modified
17 June 2026
KEV Added
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Patch
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CVSS Score v3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.1548 96.4th percentile
Risk Priority 70 floored blend · peak EPSS

Summary

CVE-2026-45657 is a critical-severity Heap-based Buffer Overflow (CWE-122) vulnerability in Microsoft Windows 11 23H2. Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 3.6% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

Use after free in Windows Kernel allows an unauthorized attacker to execute code over a network.

CWE(s)
CWE-122CWE-416

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
attack.mitre.org →
Why these techniques?

Remote kernel UAF directly enables RCE over network, mapping to exploitation of remote/public-facing services.

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

Affected Assets

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

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

SI-16 Memory Protection
addresses: CWE-416

Use-after-free exploits that achieve arbitrary code execution are blocked or significantly hardened by non-executable pages and ASLR.

References