known ransomware use

VMware ESXi OpenSLP Use-After-Free Vulnerability

Added to KEV
2021-11-03
Federal due date
2022-05-03
Vendor
VMware
Product
ESXi
EPSS
99.6th percentile (score 0.903, as of 2026-06-08)
NVD CVSS v3.1
Ransomware use
Known
Upstream
https://nvd.nist.gov/vuln/detail/CVE-2020-3992

CISA short description

VMware ESXi OpenSLP contains a use-after-free vulnerability that allows an attacker residing in the management network with access to port 427 to perform 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.