CVE-2021-21985
VMware vCenter Server Improper Input Validation Vulnerability
Does this matter?
Known to be exploited in the wild (CISA KEV, CISA remediation deadline 17 November 2021). Treat as an emergency change: patch or isolate now, then hunt for prior compromise.
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.
- CVSS 3.1
- 9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 100.00% probability · 100th percentile
- CISA KEV
- Listed 3 November 2021 · due 17 November 2021 · used in ransomware campaigns
- Weakness
- CWE-918, CWE-20, CWE-470
- Affected
- vmware/vcenter server · vmware/cloud foundation
- Source
- security@vmware.com
CISA notes
Apply updates per vendor instructions. https://nvd.nist.gov/vuln/detail/CVE-2021-21985
References
- http://packetstormsecurity.com/files/162812/VMware-Security-Advisory-2021-0010.htmlThird Party Advisory, VDB Entry
- http://packetstormsecurity.com/files/163487/VMware-vCenter-Server-Virtual-SAN-Health-Check-Remote-Code-Execution.htmlExploit, Third Party Advisory, VDB Entry
- https://www.vmware.com/security/advisories/VMSA-2021-0010.htmlVendor Advisory
- http://packetstormsecurity.com/files/162812/VMware-Security-Advisory-2021-0010.htmlThird Party Advisory, VDB Entry
- http://packetstormsecurity.com/files/163487/VMware-vCenter-Server-Virtual-SAN-Health-Check-Remote-Code-Execution.htmlExploit, Third Party Advisory, VDB Entry
- https://www.vmware.com/security/advisories/VMSA-2021-0010.htmlVendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-21985US Government Resource
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.