Critical severity · published Jul 16, 2021
CVE-2021-34458
Windows Kernel Remote Code Execution Vulnerability
9.9
CVSS
2.6%
EPSS
No
On KEV
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)2.6% · higher than 85% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
WS
Windows Server 2016 · Microsoft
20h2; 2004 · source: NVD
WS
Windows Server 2019 · Microsoft
All versions, or not specified · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-34458
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-34458
msrc.microsoft.com
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-34458
Patch
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-34458
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