CVE-2020-3957

Severity: high (CVSS 7.0 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% 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-367

Description

VMware Fusion (11.x before 11.5.5), VMware Remote Console for Mac (11.x and prior) and VMware Horizon Client for Mac (5.x and prior) contain a local privilege escalation vulnerability due to a Time-of-check Time-of-use (TOCTOU) issue in the service opener. Successful exploitation of this issue may allow attackers with normal user privileges to escalate their privileges to root on the system where Fusion, VMRC and Horizon Client are installed.

Affected products

VMware Fusion: from 11.0.0 before 11.5.5 — fixed in 11.5.5
VMware Horizon Server: through 5.4.0
VMware Remote Console: through 11.0.1
VMware Fusion: 11.x before 11.5.5
VMware Horizon Client for Mac: through 5.x
VMware Remote Console for Mac: through V11.x

How to fix

Upgrade to a fixed version: VMware Fusion 11.5.5. Check the vendor advisory for mitigations.

References

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