CVE-2020-3991

Severity: high (CVSS 7.1 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: 2020-10-16 · updated 2026-06-17

Description

VMware Horizon Client for Windows (5.x before 5.5.0) contains a denial-of-service vulnerability due to a file system access control issue during install time. Successful exploitation of this issue may allow an attacker to overwrite certain admin privileged files through a symbolic link attack at install time. This will result into a denial-of-service condition on the machine where Horizon Client for Windows is installed.

Affected products

VMware Horizon Server: from 5.0.0 before 5.5.0 — fixed in 5.5.0
VMware Horizon Client for Windows: VMware Horizon Client for Windows (5.x before 5.5.0)

How to fix

Upgrade to a fixed version: VMware Horizon Server 5.5.0. Check the vendor advisory for mitigations.

References

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