CVEvulnerability

CVE-2021-21985

9.8 CRITICAL Known exploited Published 2021-05-26 Modified 2026-08-12 Official page ↗

CISA Known Exploited Vulnerability

VMware vCenter Server Improper Input Validation Vulnerability — VMware vCenter Server

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.

Added to KEV
2021-11-03
Remediation due
2021-11-17
Ransomware use
Known
Required action
Apply updates per vendor instructions.
Notes
https://nvd.nist.gov/vuln/detail/CVE-2021-21985
Status
Analyzed
Published
2021-05-26
Last modified
2026-08-12
Assigner
[email protected]
CVSS 3.1 ([email protected])
9.8 CRITICAL — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS 3.1 (134c704f-9b21-4f2e-91b3-4a467353bcc0)
9.8 CRITICAL — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS 2.0 ([email protected])
10.0 HIGH — AV:N/AC:L/Au:N/C:C/I:C/A:C
Weaknesses
CWE-20, CWE-470, CWE-918

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.

Affected configurations

• vmware vcenter server 6.5 • vmware vcenter server 6.7 • vmware vcenter server 7.0 • vmware cloud foundation (>= 3.0 < 3.10.2.1) • vmware cloud foundation (>= 4.0 < 4.2.1)

Related

Weakness · CWE (3)

  • CWE-20 Improper Input Validation weakness
  • CWE-470 Use of Externally-Controlled Input to Select Classes or Code weakness
  • CWE-918 Server-Side Request Forgery weakness

References