Is CVE-2021-21985 exploited in the wild?

Yes. CVE-2021-21985 is known to be exploited in the wild, first recorded on 3 November 2021. Treat it as urgent.

How severe is CVE-2021-21985?

Critical severity, with a CVSS score of 9.8, published 3 November 2021.

Which products and versions are affected?

VMware vCenter Server; VMware vSphere Client (HTML5).

Is there a fix for CVE-2021-21985?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2021-21985 attacked?

It is attacked over the network, in a network appliance.

Am I affected by CVE-2021-21985?

Check whether anything you run is named in the advisory. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2021-21985: VMware vCenter Server Improper Input Validation Vulnerability

CVE-2021-21985 · Severity: critical · CVSS 9.8 · Exploited in the wild · Published 2021-11-03

The VMware vSphere Client (HTML5) contains a remote code execution vulnerability due to improper input validation in the Virtual SAN Health Check plug-in. A malicious actor with network access to port 443 can exploit this to execute commands with unrestricted privileges on the underlying operating system hosting vCenter Server.

Quick answers

Is CVE-2021-21985 exploited in the wild?: Yes. CVE-2021-21985 is known to be exploited in the wild, first recorded on 3 November 2021. Treat it as urgent.
How severe is CVE-2021-21985?: Critical severity, with a CVSS score of 9.8, published 3 November 2021.
Which products and versions are affected?: VMware vCenter Server; VMware vSphere Client (HTML5).
Is there a fix for CVE-2021-21985?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2021-21985 attacked?: It is attacked over the network, in a network appliance.
Am I affected by CVE-2021-21985?: Check whether anything you run is named in the advisory. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Affected products

VMware vCenter Server
VMware vSphere Client (HTML5)

Timeline

2021-11-03: disclosed
2021-11-03: kev added: Added to CISA Known Exploited Vulnerabilities Catalog
2021-11-17: other: CISA KEV due date for remediation
2021-07-13: other: Exploit code published on Packet Storm

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