CVE-2020-3959

Severity: low (CVSS 3.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-05-29 · updated 2026-06-17
Weakness: CWE-401

Description

VMware ESXi (6.7 before ESXi670-202004101-SG and 6.5 before ESXi650-202005401-SG), VMware Workstation (15.x before 15.1.0) and VMware Fusion (11.x before 11.1.0) contain a memory leak vulnerability in the VMCI module. A malicious actor with local non-administrative access to a virtual machine may be able to crash the virtual machine's vmx process leading to a partial denial of service.

Affected products

VMware ESXi: 6.5-650-201701001, 6.5-650-201703001, 6.5-650-201703002, 6.5-650-201704001, 6.5-650-201707101, 6.5-650-201707102 (+176); 6.5, 6.7
VMware Fusion: from 11.0.0 before 11.1.0 — fixed in 11.1.0
VMware Workstation: from 15.0.0 before 15.1.0 — fixed in 15.1.0
VMware ESXi: 6.7 before ESXi670-202004101-SG, 6.5 before ESXi650-202005401-SG
VMware Fusion: 11.x before 11.1.0
VMware Workstation: 15.x before 15.1.0

How to fix

Upgrade to a fixed version: VMware Fusion 11.1.0; VMware Workstation 15.1.0. Check the vendor advisory for mitigations.

References

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