Advisory ID VMSA-2019-0022.1
Advisory Severity Critical
CVSSv3 Range 9.8
Synopsis VMware ESXi and Horizon DaaS updates address OpenSLP remote code execution vulnerability (CVE-2019-5544)
Issue Date 2019-12-05
Updated On 2020-05-08
CVE(s) CVE-2019-5544
1. Impacted Products
  • VMware ESXi
  • VMware Horizon DaaS
2. Introduction
A vulnerability in OpenSLP was privately reported to VMware. Patches and workarounds are available to address this vulnerability in affected VMware products.
3. VMware ESXi and Horizon DaaS updates address OpenSLP remote code execution vulnerability (CVE-2019-5544)

OpenSLP as used in ESXi and the Horizon DaaS appliances has a heap overwrite issue. VMware has evaluated the severity of this issue to be in the Critical severity range with a maximum CVSSv3 base score of 9.8.


Known Attack Vectors:

A malicious actor with network access to port 427 on an ESXi host or on any Horizon DaaS management appliance may be able to overwrite the heap of the OpenSLP service resulting in remote code execution.



To remediate CVE-2019-5544 apply the patches listed in the 'Fixed Version' column of the 'Response Matrix' below.



Workarounds for CVE-2019-5544 have been documented in the VMware Knowledge Base articles listed in the 'Workarounds' column of the 'Response Matrix' below.


Additional Documentation:







VMware would like to thank the 360Vulcan team working with the 2019 Tianfu Cup Pwn Contest for reporting this issue to us.


Response Matrix:

Product Version Running On CVE Identifier CVSSV3 Severity Fixed Version Workarounds Additional Documents
ESXi 6.7 Any CVE-2019-5544 9.8 Critical ESXi670-201912001 KB76372 None
ESXi 6.5 Any CVE-2019-5544 9.8 Critical ESXi650-201912001
KB76372 None
ESXi 6.0 Any CVE-2019-5544 9.8 Critical ESXi600-201912001
KB76372 None
Horizon DaaS 8.x Virtual Appliance CVE-2019-5544 9.8 Critical KB76411 None
5. Change log

2019-12-05: VMSA-2019-0022 

Initial security advisory in conjunction with the release of ESXi patches on 2019-12-05.


2020-05-08: VMSA-2019-0022.1
Updated advisory after release of Horizon DaaS on 2020-05-07.

6. Contact


E-mail list for product security notifications and announcements:


This Security Advisory is posted to the following lists:



PGP key at:


VMware Security Advisories


VMware Security Response Policy


VMware Lifecycle Support Phases


VMware Security & Compliance Blog




Copyright 2019 VMware Inc. All rights reserved.


Sign up for Security Advisories

Enter your email address: