CVE-2020-3992

CRITICALNVD 9.89.8—
EchelonGraph scoreHIGH confidence

Score elevated to 9.8 because this CVE is listed on the CISA Known Exploited Vulnerabilities catalog (added 2021-11-03), indicating real-world exploitation has been confirmed by US federal agencies. NVD baseline CVSS 9.8 retained for reference. Confidence: HIGH.

Triggered by: CISA KEV (actively exploited)
Sources: cisa_kev, epss, ghsa, nvd
Trending — 3 sources updated this weekExploited in the wild
9.8EG
EchelonGraph verdictPatch nowTreat as an emergency — this is being exploited.
  • 3 internet-facing services (distinct ip:port) on record running an affected version — derived from Shodan data (© Shodan); a patched service can stay counted while its port stays open
  • Actively exploited in the wild (CISA-KEV)
  • Linked to ransomware campaigns
CISA-KEV: ExploitedEPSS PROB: 83%CVSS: 9.8Exploit: cisa kev · ssvc active · kev ransomware · epss top5pct · epss high · public exploitExposed services: 3

A fix is available — apply it.

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.

Internet exposure · derived from Shodan data

3 internet-facing services (distinct ip:port) on record running a version that maps to CVE-2020-3992, in our KEV-Exposure radar’s Shodan-derived sample.

across 3 countries (China, India, Iran, Islamic Republic of)top: esxi🔒 ransomware-linked
See the KEV-Exposure radar →Derived from Shodan data. Shodan data is owned by Shodan, which holds its copyright (© Shodan). EchelonGraph claims no ownership of it or copyright in it. Aggregate, host-redacted.

How it counts: every 12 hours, when Shodan query credits allow, the radar runs one Shodan query per tracked product, reads up to 100 ip:port services per query, and keeps a service when its banner version matches a CISA-KEV or high-EPSS CVE; a service is dropped when neither a search nor a Shodan InternetDB port re-check has refreshed it for 21 days. A re-check that finds the port still listed by Shodan InternetDB refreshes the service without re-reading the banner, so a patched service can stay counted while its port stays open. A count is a banner-version inference over a sample, not an exploit test and not an internet-wide census, and the unit is a service, not a machine: a machine answering on two ports counts twice.

CVSS v3
9.8
EG Score
9.8CRITICALhigh confidence
EG Risk
99
EG Risk 99/100CISA SSVC

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity98% × 45%
Exploitation100% × 40%
Automatability100% × 15%
CISA SSVC: Attend at low mission impact; Act at medium or high.
Action: A fix is available. Apply it sooner than your standard update timelines at low mission impact and as soon as possible at medium or high.
EPSS PROB
83%
EPSS %ILE
99th
KEV
⚠ Exploited

CISA SSVCAttend at low mission impact; Act at medium or high.

A fix is available. Apply it sooner than your standard update timelines at low mission impact and as soon as possible at medium or high.

Exploitation active (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table

Published

October 20, 2020

Last Modified

August 12, 2026

Advisory Details (4)

Auto-updated Sep 30, 2026
⚠️ Active exploitation confirmed. Patch available. Sources: cisa.
cisa Patch Available🔴 Active Exploitation

Known Exploited Vulnerabilities Catalog | CISA

Known Exploited Vulnerabilities Catalog | CISA. Listed in CISA Known Exploited Vulnerabilities catalog.

https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-3992
generic

ZDI-20-1385 - TrendAI™ Zero Day Initiative™ (ZDI)

https://www.zerodayinitiative.com/advisories/ZDI-20-1385/
generic

ZDI-20-1377 - TrendAI™ Zero Day Initiative™ (ZDI)

https://www.zerodayinitiative.com/advisories/ZDI-20-1377/
generic

Support Content Notification - Support Portal - Broadcom support portal

https://www.vmware.com/security/advisories/VMSA-2020-0023.html

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 48× in last 7d / 218× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 914 total refreshes for this CVE.

  1. 2026-10-05 21:15 UTCEG score recompute
  2. 2026-10-05 21:14 UTCGHSA enrichment
  3. 2026-10-05 17:40 UTCEPSS rescore
  4. 2026-10-05 17:13 UTCGHSA enrichment
  5. 2026-10-05 13:14 UTCGHSA enrichment
  6. 2026-10-05 09:13 UTCGHSA enrichment
  7. 2026-10-05 05:15 UTCGHSA enrichment
  8. 2026-10-05 01:16 UTCGHSA enrichment
  9. 2026-10-04 21:18 UTCGHSA enrichment
  10. 2026-10-04 17:19 UTCGHSA enrichment
  11. 2026-10-04 13:20 UTCGHSA enrichment
  12. 2026-10-04 09:22 UTCGHSA enrichment
  13. 2026-10-04 05:23 UTCGHSA enrichment
  14. 2026-10-04 01:25 UTCGHSA enrichment
  15. 2026-10-03 21:24 UTCGHSA enrichment
  16. 2026-10-03 17:25 UTCGHSA enrichment
  17. 2026-10-03 13:27 UTCGHSA enrichment
  18. 2026-10-03 09:28 UTCGHSA enrichment
  19. 2026-10-03 05:28 UTCGHSA enrichment
  20. 2026-10-03 01:29 UTCGHSA enrichment
  21. 2026-10-02 21:31 UTCGHSA enrichment
  22. 2026-10-02 17:33 UTCGHSA enrichment
  23. 2026-10-02 13:34 UTCGHSA enrichment
  24. 2026-10-02 09:35 UTCGHSA enrichment
  25. 2026-10-02 05:36 UTCGHSA enrichment
Show 75 more
  1. 2026-10-02 01:36 UTCGHSA enrichment
  2. 2026-10-01 21:38 UTCEG score recompute
  3. 2026-10-01 21:38 UTCGHSA enrichment
  4. 2026-10-01 19:46 UTCEPSS rescore
  5. 2026-10-01 17:36 UTCGHSA enrichment
  6. 2026-10-01 13:36 UTCGHSA enrichment
  7. 2026-10-01 09:38 UTCGHSA enrichment
  8. 2026-10-01 05:39 UTCGHSA enrichment
  9. 2026-10-01 01:41 UTCGHSA enrichment
  10. 2026-09-30 21:42 UTCGHSA enrichment
  11. 2026-09-30 17:44 UTCGHSA enrichment
  12. 2026-09-30 13:46 UTCGHSA enrichment
  13. 2026-09-30 09:44 UTCGHSA enrichment
  14. 2026-09-30 05:46 UTCGHSA enrichment
  15. 2026-09-30 01:46 UTCGHSA enrichment
  16. 2026-09-29 21:48 UTCGHSA enrichment
  17. 2026-09-29 17:47 UTCGHSA enrichment
  18. 2026-09-29 13:40 UTCGHSA enrichment
  19. 2026-09-29 09:40 UTCGHSA enrichment
  20. 2026-09-29 05:39 UTCGHSA enrichment
  21. 2026-09-29 01:41 UTCGHSA enrichment
  22. 2026-09-28 21:43 UTCEG score recompute
  23. 2026-09-28 21:43 UTCGHSA enrichment
  24. 2026-09-28 17:44 UTCGHSA enrichment
  25. 2026-09-28 13:43 UTCGHSA enrichment
  26. 2026-09-28 09:44 UTCGHSA enrichment
  27. 2026-09-28 05:45 UTCGHSA enrichment
  28. 2026-09-28 01:47 UTCGHSA enrichment
  29. 2026-09-27 21:51 UTCCISA KEV update
  30. 2026-09-27 21:47 UTCGHSA enrichment
  31. 2026-09-27 17:49 UTCGHSA enrichment
  32. 2026-09-27 13:50 UTCGHSA enrichment
  33. 2026-09-27 09:51 UTCGHSA enrichment
  34. 2026-09-27 05:52 UTCGHSA enrichment
  35. 2026-09-27 01:53 UTCGHSA enrichment
  36. 2026-09-26 21:51 UTCGHSA enrichment
  37. 2026-09-26 17:52 UTCGHSA enrichment
  38. 2026-09-26 13:52 UTCGHSA enrichment
  39. 2026-09-26 09:52 UTCGHSA enrichment
  40. 2026-09-26 05:50 UTCGHSA enrichment
  41. 2026-09-26 01:47 UTCGHSA enrichment
  42. 2026-09-25 21:49 UTCGHSA enrichment
  43. 2026-09-25 19:35 UTCCISA KEV update
  44. 2026-09-25 17:49 UTCGHSA enrichment
  45. 2026-09-25 14:55 UTCCISA KEV update
  46. 2026-09-25 13:51 UTCGHSA enrichment
  47. 2026-09-25 09:51 UTCGHSA enrichment
  48. 2026-09-25 05:52 UTCGHSA enrichment
  49. 2026-09-25 01:54 UTCGHSA enrichment
  50. 2026-09-24 21:54 UTCGHSA enrichment
  51. 2026-09-24 19:31 UTCCISA KEV update
  52. 2026-09-24 17:53 UTCEG score recompute
  53. 2026-09-24 17:53 UTCGHSA enrichment
  54. 2026-09-24 14:00 UTCEPSS rescore
  55. 2026-09-24 13:54 UTCGHSA enrichment
  56. 2026-09-24 09:55 UTCGHSA enrichment
  57. 2026-09-24 05:57 UTCGHSA enrichment
  58. 2026-09-24 01:58 UTCGHSA enrichment
  59. 2026-09-23 22:00 UTCGHSA enrichment
  60. 2026-09-23 18:01 UTCGHSA enrichment
  61. 2026-09-23 14:02 UTCEG score recompute
  62. 2026-09-23 14:02 UTCGHSA enrichment
  63. 2026-09-23 10:04 UTCGHSA enrichment
  64. 2026-09-23 06:05 UTCGHSA enrichment
  65. 2026-09-23 02:06 UTCGHSA enrichment
  66. 2026-09-22 22:07 UTCGHSA enrichment
  67. 2026-09-22 19:36 UTCCISA KEV update
  68. 2026-09-22 18:08 UTCEG score recompute
  69. 2026-09-22 18:08 UTCGHSA enrichment
  70. 2026-09-22 14:44 UTCEPSS rescore
  71. 2026-09-22 14:09 UTCGHSA enrichment
  72. 2026-09-22 10:10 UTCGHSA enrichment
  73. 2026-09-22 06:11 UTCGHSA enrichment
  74. 2026-09-22 02:13 UTCGHSA enrichment
  75. 2026-09-21 22:12 UTCEG score recompute

Publicly available exploits

(2 references)

Working exploit code is in the public domain (2 GitHub PoCs). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

  • GitHub PoCdgh05t/VMware_ESXI_OpenSLP_PoCs
    First seen Feb 4, 2021

    CVE-2020-3992 & CVE-2019-5544

    Open source ↗
  • GitHub PoCHynekPetrak/CVE-2019-5544_CVE-2020-3992
    First seen Dec 1, 2020

    Python / scapy module implementing SRVLOC/SLP protocol and scans for enabled OpenSLP services.

    Open source ↗

Related CVEs(same CWE)

Frequently asked(6)

What is CVE-2020-3992?
CVE-2020-3992 is a critical vulnerability published on October 20, 2020. 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…
When was CVE-2020-3992 disclosed?
CVE-2020-3992 was first published on October 20, 2020, with the most recent update on August 12, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2020-3992 actively exploited?
Yes. CISA added CVE-2020-3992 to the Known Exploited Vulnerabilities catalog on November 3, 2021, affecting VMware ESXi. KEV listing indicates confirmed exploitation in the wild; this CVE warrants immediate attention. A fix is available. Apply it.
What is the CVSS score of CVE-2020-3992?
CVE-2020-3992 has a CVSS v3 base score of 9.8 (NVD).
Which products are affected by CVE-2020-3992?
CVE-2020-3992 affects VMware ESXi.
How do I remediate CVE-2020-3992?
A fix for CVE-2020-3992 is available: update to the fixed version the vendor names in its advisory.

Dependency Blast Radius

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