Critical severity · published May 26, 2021
CVE-2021-21985
VMware vCenter Server Improper Input Validation Vulnerability
RansomwareIn wildKEV
9.8
CVSS
100%
EPSS
Yes
On KEV
Description
The vSphere Client (HTML5) contains a remote code execution vulnerability due to lack of input validation in the Virtual SAN Health Check plug-in which is enabled by default in vCenter Server. A malicious actor with network access to port 443 may exploit this issue to execute commands with unrestricted privileges on the underlying operating system that hosts vCenter Server.
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)100.0% · higher than 100% of CVEs
Exploited in the wildYes
CISA KEVListed Nov 3, 2021
Federal remediation dueNov 17, 2021
Ransomware campaign useKnown
Affected products
Which versions
VS
vCenter Server · VMware
6.5; 6.5; 6.5; 6.5; 6.5; 6.5; +34 more · source: NVD, KEV
VV
VMware vCenter Server and VMware Cloud Foundation ·
VMware vCenter Server (7.x before 7.0 U2b, 6.7 before 6.7 U3n, 6.5 before 6.5 U3p) and VMware Cloud Foundation (4.x before 4.2.1, 3.x before 3.10.2.1) · source: vendor
CF
Cloud Foundation · Vmware
3.0 before 3.10.2.1; 4.0 before 4.2.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-21985
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-21985
CISA KEV catalogue
https://www.cisa.gov/known-exploited-vulnerabilities-catalog
x_refsource_MISC
https://www.vmware.com/security/advisories/VMSA-2021-0010.html
x_refsource_MISC
http://packetstormsecurity.com/files/162812/VMware-Security-Advisory-2021-0010.html
x_refsource_MISC
http://packetstormsecurity.com/files/163487/VMware-vCenter-Server-Virtual-SAN-Health-Check-Remote-Code-Execution.html
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