CVE-2019-5544

CRITICALNVD 9.89.8
EchelonGraph scoreHIGH confidence

“—” beside the score: it is equal to NVD's CVSS score.

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 Known Exploited Vulnerabilities catalog, EPSS, GitHub Security Advisory, NVD CVSS v3
Exploited in the wild

Also known asEUVD-2019-15119 (ENISA EUVD) · GHSA-4734-5452-r5fh (GitHub Security Advisories)Source: ENISA EUVD

9.8EG
EchelonGraph verdictPatch nowTreat as an emergency — this is being exploited.
  • Actively exploited in the wild (CISA-KEV) — the reason this is sooner than the SSVC decision on this page at low mission impact
CISA-KEV: ExploitedEPSS PROB: 98%CVSS: 9.8Exploit: Public PoCExposed services: Not assessed

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
9.8CRITICALhigh confidence
EG Risk
99
EG Risk 99/100

EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.

How it’s computed (value × EchelonGraph’s weight)
Severity98% × 45%
Impact severity (EG Severity): CVSS 9.8 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation100% × 40%
Fixed at 100% for a CISA KEV listing: EchelonGraph's rule.
Automatability100% × 15%
CISA's SSVC Automatable value: yes (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Attend at low mission impact; Act at medium or high.
Exploitation active (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
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
98%
EPSS %ILE
99th
KEV
⚠ Exploited

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

The EG score (9.8): severity, escalated by confirmed exploitation. This CVE's 9.8 is its impact severity (EG Severity), not escalated.

EG Severity
9.8 CRITICALCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
98% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-12). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
CISA KEV and EG-KEV Tier 1 (exploited in the wild)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Act at medium mission impactAttend at low mission impact; Act at medium or high.CISA BOD 26-04: 3 days & forensic triage if the affected system is publicly exposed; 3 days & forensic triage if it is not.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Attend 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). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

BOD 26-04 (CISA's remediation timeline, Table 1)3 days & forensic triage if the affected system is publicly exposed; 3 days & forensic triage if it is not.

The score's inputs: In CISA KEV yes (CISA's KEV catalog) · Automatable yes (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

CISA required action“Apply updates per vendor instructions.”

Quoted verbatim from CISA's Known Exploited Vulnerabilities catalog. CISA directs it at US federal civilian executive branch agencies under Binding Operational Directive (BOD) 26-04, which replaced BOD 22-01 on 10 June 2026; it is not EchelonGraph's advice. CISA's notes: https://nvd.nist.gov/vuln/detail/CVE-2019-5544

Published

December 6, 2019

Last Modified

October 30, 2025

Advisory Details (8)

Auto-updated Nov 6, 2026
⚠️ Actively exploited (CISA KEV, CISA Vulnrichment). Patch available. Sources: redhat.
Web page

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
Web page

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
Web page

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

https://security.gentoo.org/glsa/202005-12
Web page

[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/
Web page

[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/
Red HatMentions a patch (unverified)

Affected: Red Hat Enterprise Linux 6.

https://access.redhat.com/errata/RHSA-2020:0199
Red HatMentions a patch (unverified)

Affected: Red Hat Enterprise Linux 7.

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

Support Content Notification - Support Portal - Broadcom support portal

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

Vendor Advisories for CVE-2019-5544(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(3)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
ubuntuslptool (1.2.1-11ubuntu0.16.04.2) @ xenial2026-11-11ubuntu
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.

Affected Packages

(1 across 1 ecosystem)
Debian:8(1)
PackageVulnerable rangeFix by version rangeDependents
openslp-dfsg1.2.1-10, 1.2.1-10+deb8u1
  • every version up to 1.2.1-10+deb8u2: fixed in 1.2.1-10+deb8u2
—

Weakness Classification(1)

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

Additional Vendor Advisories

(3)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 0× in last 7d / 0× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed its CVE.org record (CNA or CISA ADP). An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). "EchelonGraph re-scored" is our own recompute of this CVE's score, not an update from a source, and is not counted in the refreshes above. Most recent first.

  1. 2026-11-12 18:28 UTCEchelonGraph re-scored
  2. 2026-11-12 18:28 UTCVendor advisory
  3. 2026-11-12 18:28 UTCGHSA enrichmentGHSA-4734-5452-r5fh · GitHub severity HIGH · GitHub CVSS 9.8
  4. 2026-11-11 20:11 UTCEchelonGraph re-scored
  5. 2026-11-11 20:11 UTCVendor advisory
  6. 2026-11-11 20:11 UTCGHSA enrichmentGHSA-4734-5452-r5fh · GitHub severity HIGH · GitHub CVSS 9.8
  7. 2026-11-11 16:30 UTCEPSS rescoreEPSS 98% · 99th percentile
  8. 2026-11-10 21:52 UTCEchelonGraph re-scored
  9. 2026-11-10 21:52 UTCGHSA enrichmentGHSA-4734-5452-r5fh · GitHub severity HIGH · GitHub CVSS 9.8
  10. 2026-11-09 23:35 UTCEchelonGraph re-scored
  11. 2026-11-09 23:35 UTCVendor advisory
  12. 2026-11-09 23:35 UTCGHSA enrichmentGHSA-4734-5452-r5fh · GitHub severity HIGH · GitHub CVSS 9.8
  13. 2026-11-09 01:18 UTCEchelonGraph re-scored
  14. 2026-11-09 01:18 UTCVendor advisory
  15. 2026-11-09 01:18 UTCGHSA enrichmentGHSA-4734-5452-r5fh · GitHub severity HIGH · GitHub CVSS 9.8
  16. 2026-11-08 03:01 UTCEchelonGraph re-scored
  17. 2026-11-08 03:01 UTCVendor advisory
  18. 2026-11-08 03:01 UTCGHSA enrichmentGHSA-4734-5452-r5fh · GitHub severity HIGH · GitHub CVSS 9.8
  19. 2026-11-07 04:43 UTCEchelonGraph re-scored
  20. 2026-11-07 04:43 UTCVendor advisory
  21. 2026-11-07 04:43 UTCGHSA enrichmentGHSA-4734-5452-r5fh · GitHub severity HIGH · GitHub CVSS 9.8
  22. 2026-11-06 06:26 UTCEchelonGraph re-scored
  23. 2026-11-06 06:26 UTCVendor advisory
  24. 2026-11-06 06:26 UTCGHSA enrichmentGHSA-4734-5452-r5fh · GitHub severity HIGH · GitHub CVSS 9.8
  25. 2026-11-05 08:08 UTCEchelonGraph re-scored
Show 75 more
  1. 2026-11-05 08:08 UTCVendor advisory
  2. 2026-11-05 08:08 UTCGHSA enrichmentGHSA-4734-5452-r5fh · GitHub severity HIGH · GitHub CVSS 9.8
  3. 2026-11-04 16:29 UTCEPSS rescoreEPSS 98% · 99th percentile
  4. 2026-11-04 09:50 UTCEchelonGraph re-scored
  5. 2026-11-04 09:50 UTCVendor advisory
  6. 2026-11-04 09:50 UTCGHSA enrichmentGHSA-4734-5452-r5fh · GitHub severity HIGH · GitHub CVSS 9.8
  7. 2026-11-03 11:32 UTCEchelonGraph re-scored
  8. 2026-11-03 11:32 UTCVendor advisory
  9. 2026-11-03 11:32 UTCGHSA enrichmentGHSA-4734-5452-r5fh · GitHub severity HIGH · GitHub CVSS 9.8
  10. 2026-11-02 13:13 UTCEchelonGraph re-scored
  11. 2026-11-02 13:13 UTCVendor advisory
  12. 2026-11-02 13:13 UTCGHSA enrichmentGHSA-4734-5452-r5fh · GitHub severity HIGH · GitHub CVSS 9.8
  13. 2026-11-01 14:54 UTCVendor advisory
  14. 2026-11-01 14:54 UTCGHSA enrichmentGHSA-4734-5452-r5fh · GitHub severity HIGH · GitHub CVSS 9.8
  15. 2026-10-31 16:37 UTCEchelonGraph re-scored
  16. 2026-10-31 16:37 UTCVendor advisory
  17. 2026-10-31 16:37 UTCGHSA enrichmentGHSA-4734-5452-r5fh · GitHub severity HIGH · GitHub CVSS 9.8
  18. 2026-10-30 18:21 UTCEchelonGraph re-scored
  19. 2026-10-30 18:21 UTCVendor advisory
  20. 2026-10-30 18:21 UTCGHSA enrichmentGHSA-4734-5452-r5fh · GitHub severity HIGH · GitHub CVSS 9.8
  21. 2026-10-30 16:29 UTCEPSS rescoreEPSS 98% · 99th percentile
  22. 2026-10-29 20:04 UTCEchelonGraph re-scored
  23. 2026-10-29 20:04 UTCVendor advisory
  24. 2026-10-29 20:04 UTCGHSA enrichmentGHSA-4734-5452-r5fh · GitHub severity HIGH · GitHub CVSS 9.8
  25. 2026-10-28 21:46 UTCEchelonGraph re-scored
  26. 2026-10-28 21:46 UTCVendor advisory
  27. 2026-10-28 21:46 UTCGHSA enrichmentGHSA-4734-5452-r5fh · GitHub severity HIGH · GitHub CVSS 9.8
  28. 2026-10-27 23:27 UTCEchelonGraph re-scored
  29. 2026-10-27 23:27 UTCVendor advisory
  30. 2026-10-27 23:27 UTCGHSA enrichmentGHSA-4734-5452-r5fh · GitHub severity HIGH · GitHub CVSS 9.8
  31. 2026-10-27 01:08 UTCEchelonGraph re-scored
  32. 2026-10-27 01:08 UTCVendor advisory
  33. 2026-10-27 01:08 UTCGHSA enrichmentGHSA-4734-5452-r5fh · GitHub severity HIGH · GitHub CVSS 9.8
  34. 2026-10-26 02:51 UTCVendor advisory
  35. 2026-10-26 02:50 UTCGHSA enrichmentGHSA-4734-5452-r5fh · GitHub severity HIGH · GitHub CVSS 9.8
  36. 2026-10-25 18:57 UTCEchelonGraph re-scored
  37. 2026-10-25 16:27 UTCEPSS rescoreEPSS 98% · 99th percentile
  38. 2026-10-25 04:33 UTCEchelonGraph re-scored
  39. 2026-10-25 04:33 UTCVendor advisory
  40. 2026-10-25 04:33 UTCGHSA enrichmentGHSA-4734-5452-r5fh · GitHub severity HIGH · GitHub CVSS 9.8
  41. 2026-10-24 06:16 UTCEchelonGraph re-scored
  42. 2026-10-24 06:16 UTCVendor advisory
  43. 2026-10-24 06:16 UTCGHSA enrichmentGHSA-4734-5452-r5fh · GitHub severity HIGH · GitHub CVSS 9.8
  44. 2026-10-23 07:58 UTCEchelonGraph re-scored
  45. 2026-10-23 07:58 UTCVendor advisory
  46. 2026-10-23 07:58 UTCGHSA enrichmentGHSA-4734-5452-r5fh · GitHub severity HIGH · GitHub CVSS 9.8
  47. 2026-10-22 09:41 UTCEchelonGraph re-scored
  48. 2026-10-22 09:41 UTCVendor advisory
  49. 2026-10-22 09:41 UTCGHSA enrichmentGHSA-4734-5452-r5fh · GitHub severity HIGH · GitHub CVSS 9.8
  50. 2026-10-21 16:27 UTCEPSS rescoreEPSS 98% · 99th percentile
  51. 2026-10-21 11:22 UTCEchelonGraph re-scored
  52. 2026-10-21 11:22 UTCVendor advisory
  53. 2026-10-21 11:22 UTCGHSA enrichmentGHSA-4734-5452-r5fh · GitHub severity HIGH · GitHub CVSS 9.8
  54. 2026-10-20 13:05 UTCEchelonGraph re-scored
  55. 2026-10-20 13:05 UTCVendor advisory
  56. 2026-10-20 13:05 UTCGHSA enrichmentGHSA-4734-5452-r5fh · GitHub severity HIGH · GitHub CVSS 9.8
  57. 2026-10-19 16:27 UTCEPSS rescoreEPSS 98% · 99th percentile
  58. 2026-10-19 14:45 UTCEchelonGraph re-scored
  59. 2026-10-19 14:45 UTCVendor advisory
  60. 2026-10-19 14:45 UTCGHSA enrichmentGHSA-4734-5452-r5fh · GitHub severity HIGH · GitHub CVSS 9.8
  61. 2026-10-18 16:27 UTCEPSS rescoreEPSS 97% · 99th percentile
  62. 2026-10-18 16:27 UTCVendor advisory
  63. 2026-10-18 16:27 UTCGHSA enrichmentGHSA-4734-5452-r5fh · GitHub severity HIGH · GitHub CVSS 9.8
  64. 2026-10-18 09:44 UTCEchelonGraph re-scored
  65. 2026-10-17 20:47 UTCEchelonGraph re-scored
  66. 2026-10-17 20:47 UTCVendor advisory
  67. 2026-10-17 20:47 UTCGHSA enrichmentGHSA-4734-5452-r5fh · GitHub severity HIGH · GitHub CVSS 9.8
  68. 2026-10-16 22:29 UTCEchelonGraph re-scored
  69. 2026-10-16 22:29 UTCVendor advisory
  70. 2026-10-16 22:29 UTCGHSA enrichmentGHSA-4734-5452-r5fh · GitHub severity HIGH · GitHub CVSS 9.8
  71. 2026-10-16 00:11 UTCEchelonGraph re-scored
  72. 2026-10-16 00:11 UTCVendor advisory
  73. 2026-10-16 00:11 UTCGHSA enrichmentGHSA-4734-5452-r5fh · GitHub severity HIGH · GitHub CVSS 9.8
  74. 2026-10-15 01:53 UTCEchelonGraph re-scored
  75. 2026-10-15 01:53 UTCVendor advisory

Publicly available exploits

(3 references)

Public exploit code is referenced for this CVE (1 GitHub PoC), as are 1 Nuclei detection template, 1 GitHub checker repository. A detection template checks whether a system is affected; it is not necessarily exploit code. A GitHub repository named or described as a checker or scanner checks whether a system is affected; it is not necessarily exploit code. Defenders should treat patch urgency accordingly.

  • Nucleinetwork/cves/2019/CVE-2019-5544.yaml
    Published Jul 20, 2025

    VMware ESXi SLP - Heap Overflow DoS

    Open source ↗
  • GitHub PoCdgh05t/VMware_ESXI_OpenSLP_PoCs
    Published Feb 4, 2021

    CVE-2020-3992 & CVE-2019-5544

    Open source ↗
  • GitHub checkerHynekPetrak/CVE-2019-5544_CVE-2020-3992
    Published Dec 1, 2020

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

    Open source ↗

Frequently asked(6)

What is CVE-2019-5544?
CVE-2019-5544 is a critical-severity vulnerability; its CVE record was 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 the CVE record for CVE-2019-5544 published?
The CVE record for CVE-2019-5544 was published on December 6, 2019. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of October 30, 2025; the record at its source may have been updated since.
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 attention. A fix is available. Apply it.
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 affected packages EchelonGraph has on record, with version ranges, are listed in the Affected Packages section of this page.
How do I remediate CVE-2019-5544?
A fix for CVE-2019-5544 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2019-5544 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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