CVE-2020-3992
CriticalExploitedPublic exploitOpenSLP 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.
Published Oct 20, 2020 · Updated Aug 12, 2026
Key Facts
Patch immediately- CVE-2020-3992 is a critical-severity vulnerability (CVSS 9.8 v3.1) affecting Cloud Foundation (Vmware), Esxi (Vmware).
- It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Nov 11, 2020 and is known to be used in ransomware campaigns. Public exploit code is available.
- EPSS estimates a 83% probability of exploitation in the next 30 days.
- Fixed versions are available, including Cloud Foundation 3.10.1.2, Cloud Foundation 4.1.0.1.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
CVSS v3.1
9.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
83%
Higher than 99.6% of all scored CVEs
Exploited in the wild
Yes
4 catalog listings, used by ransomware
Public exploit code
Available
Proof-of-concept or weaponized module
Get the full CVE-2020-3992 brief as a PDF
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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.
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| CISA KEV | Nov 3, 2021 | May 3, 2022 | Known |
| Industry KEV feed | Nov 11, 2020 | May 3, 2022 | Known |
| CIRCL KEV | Nov 3, 2021 | May 3, 2022 | Known |
| ENISA EUVD | Nov 3, 2021 | n/a | Not reported |
Required action: Apply updates per vendor instructions.
Affected Products
224 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| Cloud FoundationVmware | See advisory | 3.10.1.2 |
| EsxiVmware | 6.5, 6.5-2, 6.5-650-201701001, 6.5-650-201703001, 6.5-650-201703002, 6.5-650-201704001, 6.5-650-201707101, 6.5-650-201707102 | n/a |
Patched Releases
Cloud Foundation
3.10.1.2, 4.1.0.1
Timeline
Publicly disclosed
Oct 20, 2020
Added to Industry KEV feed
Nov 11, 2020
Added to CISA KEV
Nov 3, 2021
Added to CIRCL KEV
Nov 3, 2021
Added to ENISA EUVD
Nov 3, 2021
Last updated
Aug 12, 2026
Weakness Type
- CWE-416 Use After Free
References
- advisoryhttps://www.zerodayinitiative.com/advisories/ZDI-20-1377/
- advisoryhttps://www.zerodayinitiative.com/advisories/ZDI-20-1385/
- patchhttps://www.vmware.com/security/advisories/VMSA-2020-0023.html
- exploitVulnCheck exploitation report
- exploitVulnCheck exploitation report
FAQ
Common Questions.
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.
Affected: Cloud Foundation (Vmware); Esxi (Vmware) versions 6.5, 6.5-2, 6.5-650-201701001, 6.5-650-201703001, 6.5-650-201703002, 6.5-650-201704001, 6.5-650-201707101, 6.5-650-201707102. The full list is in the CVE brief.
It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Nov 11, 2020 and is known to be used in ransomware campaigns.
Yes. It was added on Nov 3, 2021 with a federal remediation due date of May 3, 2022.
Public exploit code is available.
Fixed versions are available, including Cloud Foundation 3.10.1.2, Cloud Foundation 4.1.0.1.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
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