Advisory ID VMSA-2020-0008
Advisory Severity Important
CVSSv3 Range 8.3
Synopsis VMware ESXi patches address Stored Cross-Site Scripting (XSS) vulnerability (CVE-2020-3955)
Issue Date 2020-04-28
Updated On 2020-04-28 (Initial Advisory)
CVE(s) CVE-2020-3955

1. Impacted Products

VMware ESXi

2. Introduction

A Stored Cross-Site Scripting (XSS) vulnerability in VMware ESXi was privately reported to VMware. Patches are available to address this vulnerability in affected VMware products.

3. VMware ESXi patches address Stored Cross-Site Scripting (XSS) vulnerability (CVE-2020-3955)

The VMware ESXi Host Client does not properly neutralize script-related HTML when viewing virtual machines attributes. VMware has evaluated the severity of this issue to be in the Important severity range with a maximum CVSSv3 base score of 8.3.

Known Attack Vectors:
A malicious actor with access to modify the system properties of a virtual machine from inside the guest os (such as changing the hostname of the virtual machine) may be able to inject malicious script which will be executed by a victim's browser when viewing this virtual machine via the ESXi Host Client.

To remediate CVE-2020-3955 apply the updates listed in the 'Fixed Version' column of the 'Response Matrix' below.


Additional Documentation:



VMware would like to thank Benny Husted, zixian, and DAWUSHI for independently reporting this issue to us.

Product Version Running On CVE Identifier CVSSV3 Severity Fixed Version Workarounds Additional Documentation
ESXi 7.0 Any CVE-2020-3955
N/A N/A Unaffected N/A N/A
ESXi 6.7 Any CVE-2020-3955 8.3 Important ESXi670-202004103-SG None None
ESXi 6.5 Any CVE-2020-3955 8.3 Important ESXi650-201912104-SG None None

5. Change log

2020-04-28 VMSA-2020-0008
Initial security advisory.

6. Contact


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