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

CVE-2021-21985: Used in ransomware campaigns — CISA KEV

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

CISA KEV — Actively Exploited

The vSphere Client (HTML5) contains a remote code execution vulnerability due to lack of input validation in the Virtual

Vendor / Product
— / VMware / vCenter Server
Added to KEV
2021-11-03
BOD 22-01 due
Ransomware use
Known
CVSS / EPSS
10.0 CISA · EPSS 100.00%

01What CISA says about 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.

02Required action — verbatim from CISA

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

03Notes & references

04SARA's analyst layer — why this matters

This vulnerability is currently on the CISA KEV list, which CISA only adds CVEs to when there is reliable evidence of active exploitation in the wild. For federal civilian agencies, BOD 22-01 requires remediation by the due date above. For everyone else, KEV is the strongest "patch immediately" signal you can get from public threat intel.

05Affected products (summary)

No structured affected-product list available — see references below for vendor advisories.

06Detection

Open the Sigma generator with a pre-filled prompt for this CVE to draft a starting detection:

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