Priority reviewCritical

CVE-2026-47291

Microsoft Windows 10 Version 1607, Windows 10 Version 1809, Windows 10 Version 21H2

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

PRIORITY ASSESSMENT

FIRST EPSS indicates an elevated probability of exploitation.

Known exploitationNot established by KEV

Exploit probability22.8%

Technical severityCVSS 9.8

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

Product: Microsoft Windows 10 Version 1607, Windows 10 Version 1809, Windows 10 Version 21H2
Affected versions: >= 10.0.14393.0 < 10.0.14393.9234, >= 10.0.17763.0 < 10.0.17763.8880, >= 10.0.19044.0 < 10.0.19044.7417, >= 10.0.19045.0 < 10.0.19045.7417, >= 10.0.22631.0 < 10.0.22631.7219, >= 10.0.26100.0 < 10.0.26100.8655, >= 10.0.26200.0 < 10.0.26200.8655, >= 10.0.28000.0 < 10.0.28000.2269, >= 6.2.9200.0 < 6.2.9200.26132, >= 6.3.9600.0 < 6.3.9600.23228, >= 10.0.20348.0 < 10.0.20348.5256, >= 10.0.26100.0 < 10.0.26100.32995, < 10.0.14393.9234, < 10.0.17763.8880, < 10.0.19044.7417, < 10.0.19045.7417, < 10.0.22631.7219, < 10.0.26100.8655, < 10.0.26200.8655, < 10.0.28000.2269
Fixed versions: 10.0.14393.9234, 10.0.17763.8880, 10.0.19044.7417, 10.0.19045.7417, 10.0.22631.7219, 10.0.26100.8655, 10.0.26200.8655, 10.0.28000.2269, 10.0.20348.5256, 10.0.26100.32995

Confirm exposure before applying a vendor-supported change.

1
Identify
Confirm that Microsoft Windows 10 Version 1607, Windows 10 Version 1809, Windows 10 Version 21H2 and an affected version are present.
2
Prioritize
Combine exploitation signals with asset exposure and business criticality.
3
Remediate
Follow the vendor advisory or supported update path and preserve rollback options.
4
Verify
Recheck the version, service health, access paths, and relevant logs.