CVE-2025-27473

HTTP.sys Denial of Service Vulnerability

State: Published
Severity: 7.5 High
Published: Apr 8, 2025
Updated: Aug 10, 2026
Reserved: Feb 26, 2025

Description

Uncontrolled resource consumption in Windows HTTP.sys allows an unauthorized attacker to deny service over a network.

Scores

CVSS	Score	Vector	Source
3.1	7.5 High	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C	microsoft

Weaknesses

CWE-400 Uncontrolled Resource Consumption

Affected Products

Product	Versions
Windows 10 Version 1507Microsoft	10.0.10240.0 to before 10.0.10240.20978Affected
Windows 10 Version 1607Microsoft	10.0.14393.0 to before 10.0.14393.7969Affected
Windows 10 Version 1809Microsoft	10.0.17763.0 to before 10.0.17763.7136Affected
Windows 10 Version 21H2Microsoft	10.0.19044.0 to before 10.0.19044.5737Affected
Windows 10 Version 22H2Microsoft	10.0.19045.0 to before 10.0.19045.5737Affected
Windows 11 version 22H2Microsoft	10.0.22621.0 to before 10.0.22621.5189Affected
Windows 11 version 22H3Microsoft	10.0.22631.0 to before 10.0.22631.5189Affected
Windows 11 Version 23H2Microsoft	10.0.22631.0 to before 10.0.22631.5189Affected
Windows 11 Version 24H2Microsoft	10.0.26100.0 to before 10.0.26100.3775Affected
Windows Server 2008 R2 Service Pack 1Microsoft	6.1.7601.0 to before 6.1.7601.27670Affected
Windows Server 2008 R2 Service Pack 1 (Server Core installation)Microsoft	6.1.7601.0 to before 6.1.7601.27670Affected
Windows Server 2008 Service Pack 2Microsoft	6.0.6003.0 to before 6.0.6003.23220Affected
Windows Server 2008 Service Pack 2 (Server Core installation)Microsoft	6.0.6003.0 to before 6.0.6003.23220Affected
Windows Server 2012Microsoft	6.2.9200.0 to before 6.2.9200.25423Affected
Windows Server 2012 (Server Core installation)Microsoft	6.2.9200.0 to before 6.2.9200.25423Affected
Windows Server 2012 R2Microsoft	6.3.9600.0 to before 6.3.9600.22523Affected
Windows Server 2012 R2 (Server Core installation)Microsoft	6.3.9600.0 to before 6.3.9600.22523Affected
Windows Server 2016Microsoft	10.0.14393.0 to before 10.0.14393.7969Affected
Windows Server 2016 (Server Core installation)Microsoft	10.0.14393.0 to before 10.0.14393.7969Affected
Windows Server 2019Microsoft	10.0.17763.0 to before 10.0.17763.7136Affected
Windows Server 2019 (Server Core installation)Microsoft	10.0.17763.0 to before 10.0.17763.7136Affected
Windows Server 2022Microsoft	10.0.20348.0 to before 10.0.20348.3453Affected
Windows Server 2022, 23H2 Edition (Server Core installation)Microsoft	10.0.25398.0 to before 10.0.25398.1551Affected
Windows Server 2025Microsoft	10.0.26100.0 to before 10.0.26100.3775Affected
Windows Server 2025 (Server Core installation)Microsoft	10.0.26100.0 to before 10.0.26100.3775Affected

References

HTTP.sys Denial of Service Vulnerabilityvendor-advisorypatch

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