CVE-2021-21985

VMware vCenter Server and VMware Cloud Foundation

Published 26 May 2021 · updated 12 Aug 2026 · Analyzed

9.8 Critical · CVSS 3.1, NVD

Exploited in the wild

CISA added this to its Known Exploited Vulnerabilities catalog on 3 Nov 2021, with a remediation deadline of 17 Nov 2021 for US federal agencies. It has been used in ransomware campaigns.

Required action: Apply updates per vendor instructions.

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.

References

packetstormsecurity.com/files/162812/VMware-Security-Advisory-2021-0010.html · Third Party Advisory, VDB Entry
packetstormsecurity.com/files/163487/VMware-vCenter-Server-Virtual-SAN-Health-Check-Remote-Code-Execution.html · Exploit, Third Party Advisory, VDB Entry
www.vmware.com/security/advisories/VMSA-2021-0010.html · Vendor Advisory
www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-21985 · US Government Resource