CVE-2021-21985The 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.
Updated under an hour ago ()
Does this affect you?
It affects vmware vcenter_server and 1 other product. Add what you run to find out whether that includes you.
CISA lists it as known exploited since Nov 3, 2021; federal agencies had to remediate by Nov 17, 2021, and it is known to be used in ransomware. Treat that date as your deadline.
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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.
- CVSS
- 9.8 CRITICAL (v3.1, CISA ADP)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Weakness (CWE)
- CWE-20, CWE-470, CWE-918
- Known exploited
- Added to CISA KEV Nov 3, 2021; federal remediation due Nov 17, 2021; known ransomware useApply updates per vendor instructions.
- EPSS (exploitation in the next 30 days)
- 100.00% (percentile 100)
- Assigned by
- vmware
- NVD analysis
- Analyzed
- Record last updated
- Aug 12, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
vmware vcenter_server vmware:vcenter_server | 6.5; 6.5; 6.5; 6.5; 6.5; 6.5; 6.5; 6.5; and 43 more ranges | NVD |
vmware cloud_foundation vmware:cloud_foundation | from 3.0 before 3.10.2.1; from 4.0 before 4.2.1 | NVD |
References
- https://www.vmware.com/security/advisories/VMSA-2021-0010.htmlx-refsource-misc, vendor-advisory
- http://packetstormsecurity.com/files/162812/VMware-Security-Advisory-2021-0010.htmlx-refsource-misc, third-party-advisory, vdb-entry
- http://packetstormsecurity.com/files/163487/VMware-vCenter-Server-Virtual-SAN-Health-Check-Remote-Code-Execution.htmlx-refsource-misc, exploit, third-party-advisory, vdb-entry
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-21985us-government-resource
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.