Critical severity · published May 11, 2021
CVE-2021-31166
HTTP Protocol Stack Remote Code Execution Vulnerability
In wildKEV
9.8
CVSS
99.9%
EPSS
Yes
On KEV
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)99.9% · higher than 100% of CVEs
Exploited in the wildYes
CISA KEVListed Apr 6, 2022
Federal remediation dueApr 27, 2022
Ransomware campaign useNot known
Affected products
Which versions
W1
Windows 10 Version 2004 · Microsoft
10.0.0 before 10.0.19041.982 · source: vendor
W1
Windows 10 Version 20H2 · Microsoft
10.0.0 before 10.0.19042.982 · source: vendor
WS
Windows Server version 2004 · Microsoft
10.0.0 before 10.0.19041.982 · source: vendor
WS
Windows Server version 20H2 · Microsoft
10.0.0 before 10.0.19042.982 · source: vendor
W1
Windows 10 2004 · Microsoft
before 10.0.19041.982 · source: NVD
W1
Windows 10 20h2 · Microsoft
before 10.0.19042.982 · source: NVD
WS
Windows Server 2004 · Microsoft
before 10.0.19041.982 · source: NVD
WS
Windows Server 20h2 · Microsoft
before 10.0.19042.982 · source: NVD
HP
HTTP Protocol Stack · Microsoft
All versions, or not specified · source: KEV
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-31166
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-31166
CISA KEV catalogue
https://www.cisa.gov/known-exploited-vulnerabilities-catalog
x_refsource_MISC
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31166
x_refsource_MISC
http://packetstormsecurity.com/files/162722/Microsoft-HTTP-Protocol-Stack-Remote-Code-Execution.html
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