CVE WatchAug 12, 2026

CVE-2020-3992

VMware ESXi OpenSLP Use-After-Free Vulnerability

CVSS

9.8

Critical

EPSS

83.0%

p100

KEV

YES

Nov 3, 2021

Exploit Today

0-100

Published: Oct 20, 2020 · Last modified: Aug 12, 2026 · CWE-416

EPSS · 30d

83.0%EPSS · 30 days83.0%

2026-08-022026-08-31

KEV catalog record

Product

VMware / ESXi

Vulnerability

VMware ESXi OpenSLP Use-After-Free Vulnerability

Added to KEV

Nov 3, 2021

Remediate by

May 3, 2022

Known ransomware use

Yes

Summary description

VMware ESXi OpenSLP contains a use-after-free vulnerability that allows an attacker residing in the management network with access to port 427 to perform remote code execution.

Required action

Apply updates per vendor instructions.

Notes

https://nvd.nist.gov/vuln/detail/CVE-2020-3992

Technical description

OpenSLP as used in VMware ESXi (7.0 before ESXi_7.0.1-0.0.16850804, 6.7 before ESXi670-202010401-SG, 6.5 before ESXi650-202010401-SG) has a use-after-free issue. A malicious actor residing in the management network who has access to port 427 on an ESXi machine may be able to trigger a use-after-free in the OpenSLP service resulting in remote code execution.

Official references

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