CVE-2019-5544

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 — 5 sources updated this weekExploited in the wild
9.8EG
EchelonGraph verdictPatch nowTreat as an emergency — this is being exploited.
  • Actively exploited in the wild (CISA-KEV)
CISA-KEV: ExploitedEPSS PROB: 97%CVSS: 9.8Exploit: cisa kev · ssvc active · kev ransomware · epss top5pct · epss high · public exploitExposed: 0

A fix is available — apply it.

OpenSLP as used in ESXi and the Horizon DaaS appliances has a heap overwrite issue. VMware has evaluated the severity of this issue to be in the Critical severity range with a maximum CVSSv3 base score of 9.8.

CVSS v3
9.8
EG Score
9.8(high)
EG Risk
99(Act)
EG Risk 99/100SSVC: Act

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%
Action: Fix now — active exploitation, automatable, high impact.
EPSS PROB
97%
EPSS %ILE
100%
KEV
⚠ Exploited

Published

December 6, 2019

Last Modified

October 30, 2025

Advisory Details (8)

Auto-updated Jun 1, 2026
Patch available. Sources: redhat.
generic

oss-security - Re: CVE-2019-5544 openslp 1.2.1, 2.0.0 heap overflow vulnerability

http://www.openwall.com/lists/oss-security/2019/12/11/2
generic

oss-security - Re: CVE-2019-5544 openslp 1.2.1, 2.0.0 heap overflow vulnerability

http://www.openwall.com/lists/oss-security/2019/12/10/2
generic

OpenSLP: Multiple vulnerabilities (GLSA 202005-12) — Gentoo security

https://security.gentoo.org/glsa/202005-12
generic

[SECURITY] Fedora 31 Update: openslp-2.0.0-23.fc31 - package-announce - Fedora mailing-lists

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZPXXJZLPLAQULBCJVI5NNWZ3PGWXGXWG/
generic

[SECURITY] Fedora 30 Update: openslp-2.0.0-22.fc30 - package-announce - Fedora mailing-lists

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/DA3LYAJ2NRKMOZLZOQNDJ5TNQRFMWGHF/
redhat Patch Available

Affected: Red Hat Enterprise Linux 6.

https://access.redhat.com/errata/RHSA-2020:0199
redhat Patch Available

Affected: Red Hat Enterprise Linux 7.

https://access.redhat.com/errata/RHSA-2019:4240
generic

Support Content Notification - Support Portal - Broadcom support portal

http://www.vmware.com/security/advisories/VMSA-2019-0022.html

Patch Availability(3)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntuslptool (1.2.1-11ubuntu0.16.04.2) @ xenial2026-07-26ubuntu
redhatopenslp-1:2.0.0-4.el6_102020-01-22redhat
redhatopenslp-1:2.0.0-8.el7_72019-12-16redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Weakness Classification(1)

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

All Vendor Advisories

(4)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 55× in last 7d / 351× 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 711 total refreshes for this CVE.

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

Publicly available exploits

(3 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 ↗
  • Nucleinetwork/cves/2019/CVE-2019-5544.yaml
    First seen Jan 1, 2019

    VMware ESXi SLP - Heap Overflow DoS

    Open source ↗

Related CVEs(same vendor + same CWE)

Frequently asked(6)

What is CVE-2019-5544?
CVE-2019-5544 is a critical vulnerability published on December 6, 2019. OpenSLP as used in ESXi and the Horizon DaaS appliances has a heap overwrite issue. VMware has evaluated the severity of this issue to be in the Critical severity range with a maximum CVSSv3 base score of 9.8.
When was CVE-2019-5544 disclosed?
CVE-2019-5544 was first published in the National Vulnerability Database on December 6, 2019, with the most recent update on October 30, 2025. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2019-5544 actively exploited?
Yes. CISA added CVE-2019-5544 to the Known Exploited Vulnerabilities catalog on November 3, 2021, affecting VMware VMware ESXi and Horizon DaaS. KEV listing indicates confirmed exploitation in the wild; this CVE warrants immediate patching attention.
What is the CVSS score of CVE-2019-5544?
CVE-2019-5544 has a CVSS v3 base score of 9.8 (NVD).
Which products are affected by CVE-2019-5544?
CVE-2019-5544 affects VMware VMware ESXi and Horizon DaaS. The full affected-products list, including version ranges and fixed versions, is shown in the Affected Packages section of this page.
How do I remediate CVE-2019-5544?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2019-5544, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2019-5544

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