Go to homepageCyberStrike

Menu

Star on GitHub · 3.2k
Sign inDownload

CVE-2021-21985

9.8 · CRITICALActively Exploited

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.

Published May 26, 2021CWE-918EPSS 100.00%

Overview

CVE-2021-21985 is a critical-severity vulnerability. It was published on May 26, 2021 and has a CVSS 3.1 base score of 9.8 (CRITICAL). This vulnerability is listed in CISA's Known Exploited Vulnerabilities catalog, indicating active exploitation in the wild.

This vulnerability has a CVSS 3.1 base score of 9.8, rated CRITICAL. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.

Technical 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.

Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

References

Refpacketstormsecurity.com/files/162812/VMware-Security-Advisory-2021-0010.htmlRefpacketstormsecurity.com/files/163487/VMware-vCenter-Server-Virtual-SAN-Health-Check-Remote-Code-Execution.htmlRefwww.vmware.com/security/advisories/VMSA-2021-0010.htmlRefpacketstormsecurity.com/files/162812/VMware-Security-Advisory-2021-0010.htmlRefpacketstormsecurity.com/files/163487/VMware-vCenter-Server-Virtual-SAN-Health-Check-Remote-Code-Execution.htmlRefwww.vmware.com/security/advisories/VMSA-2021-0010.htmlCISAwww.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-21985

How CyberStrike helps

Frequently asked questions

What is CVE-2021-21985?

CVE-2021-21985 is a critical-severity vulnerability. It was published on May 26, 2021 and has a CVSS 3.1 base score of 9.8 (CRITICAL). This vulnerability is listed in CISA's Known Exploited Vulnerabilities catalog, indicating active exploitation in the wild.

How severe is CVE-2021-21985?

This vulnerability has a CVSS 3.1 base score of 9.8, rated CRITICAL. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.

How do I fix or remediate CVE-2021-21985?

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

How can CyberStrike help with CVE-2021-21985?

CyberStrike is an open-source, AI-augmented pentesting engine. Rather than flag a version number, it tests whether an issue like CVE-2021-21985 is actually reachable in your own applications and APIs, then verifies each finding before reporting it. That tells you if the weakness is a real, exploitable risk in your environment or a false positive you can safely deprioritize.

Related CRITICAL CVEs from 2021

View all
Browse by year2026202520242023202220212020201920182017201620152014201320122011201020092008200720062005200420032002200120001999