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Multiple vulnerabilities in VMware ESXi and vSphere Client

By 23 September 2021 CERT, SOC, Vulnerability
VMWare kwetsbaarheid

This blog contains information regarding multiple critical vulnerabilities in VMware ESXi and vSphere Client (HTML5). As soon as we have an update, we’ll add it to this post. More information about possible risks and details can be found at the bottom of this blog.

Update September 23, 2021

17:00 | VMware has published information regarding multiple critical vulnerabilities in VMware ESXi and vSphere Client (HTML5). Updates have been made available to resolve these vulnerabilities. VMware has published a detailed overview of the vulnerabilities on their website.

An attacker with access to the network may be able to run arbitrary system code via port 443 (CVE-2021-21972).
An attacker with network access to port 443 is able to retrieve server plugin information with the use of modified POST requests naar the vCenter server (CVE-2021-21973).
An attacker with access to the same network secment as ESXi and port 427 may be able to initiate a heap overflow in the OpenSLP service, possibly resulting in the ability to execute arbitrary system code (CVE-2021-21974).

VMware has published updates to resolve these vulnerabilities. Install these updates as soon as possible. If an update is not possible in the short term, VMware has published a temporary workaround for these issues.

Reason and background of this blog

This blog contains information about vulnerabilities, the possible risk and advice on how to prevent or limit damage. Below are the possible risks, details and background information.

Potential risk

The vulnerabilities are present in the following VMware products:

  • VMware ESXi
  • VMware vCenter Server (vCenter Server)
  • VMware Cloud Foundation (Cloud Foundation)

Detail info

VMware has published a detailed overview of the vulnerabilities on their website.

The following CVE references belong to this vulnerability:

Background

More information about this vulnerability:

VMware has published updates to resolve these vulnerabilities. Install these updates as soon as possible. If an update is not possible in the short term, VMware has published a temporary workaround for these issues.

Sources:

https://www.vmware.com/security/advisories/VMSA-2021-0002.html

https://kb.vmware.com/s/article/82374

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