High severity · published Jul 14, 2021
CVE-2021-33771
Windows Kernel Elevation of Privilege Vulnerability
In wildKEV
7.8
CVSS
10.2%
EPSS
Yes
On KEV
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)10.2% · higher than 96% of CVEs
Exploited in the wildYes
CISA KEVListed Nov 3, 2021
Federal remediation dueNov 17, 2021
Ransomware campaign useNot known
Affected products
Which versions
WI
Windows · Microsoft
All versions, or not specified · source: KEV
W1
Windows 10 Version 1507 · Microsoft
10.0.10240.0 before 10.0.10240.19003 · source: vendor
W1
Windows 10 Version 1607 · Microsoft
10.0.14393.0 before 10.0.14393.4530 · source: vendor
W1
Windows 10 Version 1809 · Microsoft
10.0.17763.0 before 10.0.17763.2061; 10.0.0 before 10.0.17763.2061 · source: vendor
W1
Windows 10 Version 1909 · Microsoft
10.0.0 before 10.0.18363.1679 · source: vendor
W1
Windows 10 Version 2004 · Microsoft
10.0.0 before 10.0.19041.1110 · source: vendor
W1
Windows 10 Version 20H2 · Microsoft
10.0.0 before 10.0.19042.1110 · source: vendor
W1
Windows 10 Version 21H1 · Microsoft
10.0.0 before 10.0.19043.1110 · source: vendor
W8
Windows 8.1 · Microsoft
6.3.0 before 6.3.9600.20069 · source: vendor, NVD
WS
Windows Server 2012 R2 · Microsoft
6.3.9600.0 before 6.3.9600.20069 · source: vendor
WS
Windows Server 2012 R2 (Server Core installation) · Microsoft
6.3.9600.0 before 6.3.9600.20069 · source: vendor
WS
Windows Server 2016 · Microsoft
10.0.14393.0 before 10.0.14393.4530 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-33771
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-33771
CISA KEV catalogue
https://www.cisa.gov/known-exploited-vulnerabilities-catalog
vendor-advisory
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-33771
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