Cyber Resilience

CVE-2026-47291

CriticalUpdated

Published: 09 June 2026

Published
09 June 2026
Modified
17 June 2026
KEV Added
Patch
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 0.2151 97.3th percentile
Risk Priority 70 floored blend · peak EPSS

Summary

CVE-2026-47291 is a critical-severity Heap-based Buffer Overflow (CWE-122) vulnerability in Microsoft Windows 10 21H2. 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 2.7% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

Integer overflow or wraparound in Windows HTTP.sys allows an unauthorized attacker to execute code over a network.

CWE(s)

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.
Why these techniques?

Remote integer overflow RCE in HTTP.sys (kernel HTTP handler) directly enables exploitation of public-facing web services.

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

Affected Assets

microsoft
windows 10 1607
≤ 10.0.14393.9234 · ≤ 10.0.14393.9234
microsoft
windows 10 1809
≤ 10.0.17763.8880 · ≤ 10.0.17763.8880
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 2012
all versions, r2
microsoft
windows server 2016
≤ 10.0.14393.9234
+3 more product configuration(s) — see NVD for full list

Mitigating Controls

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

References