VMware · ESXi
CVE-2020-3992
VMware ESXi OpenSLP Use-After-Free Vulnerability
What it is
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.
CISA: 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.
What to do
Apply updates per vendor instructions.
Deadline for US federal agencies: May 3, 2022
More exploited flaws from VMware
| Added | Vulnerability | Product | Severity | Attack chance |
|---|---|---|---|---|
| Mar 4, 2025 | Arbitrary Write | ESXi | High 8.2 | 1.0% |
| Jul 30, 2024 | Authentication Bypass | ESXi | Medium 6.8 | 27% |
| Mar 4, 2025 | TOCTOU Race Condition | ESXi and Workstation | Critical 9.3 | 1.6% |
| Mar 4, 2025 | Information Disclosure | ESXi, Workstation, and Fusion | High 7.1 | 1.6% |
| Nov 20, 2024 | Heap-Based Buffer Overflow | vCenter Server | Critical 9.8 | 55% |
| Nov 20, 2024 | Privilege Escalation | vCenter Server | High 7.5 | 17% |
| Jul 17, 2024 | Incorrect Default File Permissions Vulnerability | vCenter Server | Medium 6.5 | 13% |
| Jan 22, 2024 | Out-of-Bounds Write | vCenter Server | Critical 9.8 | 99.2% |
Sources: Known Exploited Vulnerabilities (CISA, public domain), CVE records (cve.org) and EPSS (FIRST). The chance of attacks is the EPSS estimate that someone will try to exploit the flaw in the next 30 days.