CVE-2019-5527
📋 TL;DR
This CVE describes a use-after-free vulnerability in the virtual sound device of VMware products. Successful exploitation could allow an attacker with guest OS access to execute code on the host OS. Affected products include ESXi, Workstation, Fusion, VMRC, and Horizon Client.
💻 Affected Systems
- ESXi
- Workstation
- Fusion
- VMRC
- Horizon Client
📦 What is this software?
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Esxi by Vmware
Fusion by Vmware
Horizon by Vmware
Horizon by Vmware
Horizon by Vmware
⚠️ Risk & Real-World Impact
Worst Case
An attacker with guest OS access could execute arbitrary code on the host system, potentially leading to full host compromise and lateral movement within the environment.
Likely Case
Guest-to-host escape allowing attacker to compromise the hypervisor from a compromised virtual machine.
If Mitigated
If proper network segmentation and access controls are in place, impact is limited to the affected virtual machine and host system.
🎯 Exploit Status
Requires guest OS access and knowledge of the vulnerability. No public exploits known at time of advisory.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Varies by product - see VMSA-2019-0014 for specific patched versions
Vendor Advisory: https://www.vmware.com/security/advisories/VMSA-2019-0014.html
Restart Required: Yes
Instructions:
1. Review VMSA-2019-0014 for affected versions. 2. Download and apply appropriate patches from VMware. 3. Restart affected systems as required.
🔧 Temporary Workarounds
Disable virtual sound device
allRemove or disable the virtual sound device from affected virtual machines
For ESXi: Use vSphere Client to edit VM settings and remove sound card
For Workstation/Fusion: Edit VM settings to remove sound device
🧯 If You Can't Patch
- Disable virtual sound device on all affected VMs
- Implement strict network segmentation to limit lateral movement if host is compromised
🔍 How to Verify
Check if Vulnerable:
Check VMware product version against affected versions in VMSA-2019-0014Check Version:
For ESXi: esxcli system version get; For Workstation: Help > About VMware WorkstationVerify Fix Applied:
Verify installed version matches or exceeds patched versions listed in advisory📡 Detection & Monitoring
Log Indicators:
- Unexpected process execution on host from guest context
- Crash dumps or abnormal behavior in vmx process
Network Indicators:
- Unusual network traffic from hypervisor to internal systems
SIEM Query:
Process creation where parent process is vmx or related VMware process with unusual command line