CVE-2026-47291: exploitation status and patch state

CVE-2026-47291 · CVSS 9.8 CRITICAL · EPSS 25% · patch available

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

Is CVE-2026-47291 exploited?

• Not in the CISA KEV catalog.
• EPSS puts exploitation in the next 30 days at 25%.
• Public exploit code: none found in monitored sources.

Which products and versions are affected?

• Microsoft · Windows 10 Version 1607 · >= 10.0.14393.0, < 10.0.14393.9234
• Microsoft · Windows 10 Version 1809 · >= 10.0.17763.0, < 10.0.17763.8880
• Microsoft · Windows 10 Version 21H2 · >= 10.0.19044.0, < 10.0.19044.7417
• Microsoft · Windows 10 Version 22H2 · >= 10.0.19045.0, < 10.0.19045.7417
• Microsoft · Windows 11 version 23H2 · >= 10.0.22631.0, < 10.0.22631.7219
• Microsoft · Windows 11 Version 24H2 · >= 10.0.26100.0, < 10.0.26100.8655
• Microsoft · Windows 11 Version 25H2 · >= 10.0.26200.0, < 10.0.26200.8655
• Microsoft · Windows 11 version 26H1 · >= 10.0.28000.0, < 10.0.28000.2269
• Microsoft · Windows Server 2012 · >= 6.2.9200.0, < 6.2.9200.26132
• Microsoft · Windows Server 2012 (Server Core installation) · >= 6.2.9200.0, < 6.2.9200.26132
• Microsoft · Windows Server 2012 R2 · >= 6.3.9600.0, < 6.3.9600.23228
• Microsoft · Windows Server 2012 R2 (Server Core installation) · >= 6.3.9600.0, < 6.3.9600.23228
• Microsoft · Windows Server 2016 · >= 10.0.14393.0, < 10.0.14393.9234
• Microsoft · Windows Server 2016 (Server Core installation) · >= 10.0.14393.0, < 10.0.14393.9234
• Microsoft · Windows Server 2019 · >= 10.0.17763.0, < 10.0.17763.8880
• Microsoft · Windows Server 2019 (Server Core installation) · >= 10.0.17763.0, < 10.0.17763.8880
• Microsoft · Windows Server 2022 · >= 10.0.20348.0, < 10.0.20348.5256
• Microsoft · Windows Server 2025 · >= 10.0.26100.0, < 10.0.26100.32995
• Microsoft · Windows Server 2025 (Server Core installation) · >= 10.0.26100.0, < 10.0.26100.32995
• Microsoft · Windows 10 Version 1809 for 32-bit Systems
• Microsoft · Windows 10 Version 1809 for x64-based Systems
• Microsoft · Windows Server 2022 (Server Core installation)
• Microsoft · Windows 10 Version 21H2 for 32-bit Systems
• Microsoft · Windows 10 Version 21H2 for ARM64-based Systems
• Microsoft · Windows 10 Version 21H2 for x64-based Systems
• Microsoft · Windows 11 Version 25H2 for ARM64-based Systems
• Microsoft · Windows 11 Version 25H2 for x64-based Systems
• Microsoft · Windows 11 Version 23H2 for ARM64-based Systems
• Microsoft · Windows 11 Version 23H2 for x64-based Systems
• Microsoft · Windows 11 Version 26H1 for ARM64-based Systems
• Microsoft · Windows 11 version 26H1 for x64-based Systems
• Microsoft · Windows 10 Version 1607 for 32-bit Systems
• Microsoft · Windows 10 Version 1607 for x64-based Systems

Is there a patch?

Yes. Update to one of these or later:

From Microsoft's CVE record · Microsoft advisory

• KB5094123
• KB5094128
• KB5094127
• KB5094125
• KB5094126
• KB5093998
• KB5095051
• KB5094122
• KB5094042
• KB5094041

From Microsoft's Security Update Guide · Microsoft advisory

What PlainSec published about CVE-2026-47291

• ShareFile shutdown signals more than maintenance (2026-07-13)
• Windows now has a remote-to-SYSTEM path (2026-07-10)

Primary sources

• NVD record
• Microsoft KB5094123
• Microsoft KB5094128
• Microsoft KB5094127
• Microsoft KB5094125
• Microsoft KB5094126
• Microsoft KB5093998
• Microsoft KB5095051
• Microsoft KB5094122
• Microsoft KB5094042

KEV and EPSS are re-checked daily. Record last updated 2026-10-25.