SARA / Free Tools / CVE / CVE-2021-21985

CVE-2021-21985 — VMware vCenter Server Improper Input Validation Vulnerability

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 com

CVSS
EPSS
94.41% (top 0.00%)
CWE
Published
2021-05-26T14:04:30.000Z
Last modified
2025-10-21T23:25:44.978Z
CVSS vector
CISA KEV — Actively Exploited
Added to KEV
2021-11-03
BOD 22-01 due
2021-11-17
Ransomware use
Known

01What is this vulnerability?

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.

02Affected products

VendorProductVersions
na / VMware vCenter Server and VMware Cloud FoundationVMware 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)

03Active exploitation status

Yes — actively exploited. Added to the CISA KEV catalog on 2021-11-03. Ransomware use: Known.

04Recommended remediation

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Open the Sigma generator with a pre-filled prompt for this CVE to draft a starting detection in your stack of choice:

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07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

09References

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