Applied Cybernetics Group
Threat intel → detection pipeline
Tuesday, July 14, 2026
Data as of 20:11 UTC

known ransomware use

VMware vCenter Server Improper Input Validation Vulnerability

Added to KEV
2021-11-03
Federal due date
2021-11-17
Vendor
VMware
Product
vCenter Server
EPSS
100.0th percentile (score 1.000, as of 2026-07-13)
NVD CVSS v3.1
Ransomware use
Known
Upstream
https://nvd.nist.gov/vuln/detail/CVE-2021-21985

CISA short description

VMware vSphere Client contains an improper input validation vulnerability in the Virtual SAN Health Check plug-in, which is enabled by default in vCenter Server, which allows for remote code execution.

Required action

Apply updates per vendor instructions.

EPSS percentile is the FIRST.org exploit-probability ranking as of the date noted above; it moves daily. CVSS reflects NVD's analysis at time of publication.