CVE-2026-43999

CRITICALPre-NVD 9.99.9—
EchelonGraph scoreMEDIUM confidence

This critical-severity CVE scores 9.9 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 1.0%, top 40% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
Elevated
9.9EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 9.9Exploit: Elevated riskExposed: 0

A fix is available — apply it.

vm2 is an open source vm/sandbox for Node.js. Prior to 3.11.0, NodeVM's builtin allowlist can be bypassed when the module builtin is allowed (including via the '*' wildcard). The module builtin exposes Node's Module._load(), which loads any module by name directly in the host context, completely bypassing vm2's builtin restriction. This allows sandboxed code to load excluded builtins like child_process and achieve remote code execution. This vulnerability is fixed in 3.11.0.

CVSS v3
9.9
EG Score
9.9(medium)
EG Risk
61(Track*)
EG Risk 61/100SSVC: Track*

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
Severity99% × 45%
Exploitation40% × 40%
Automatability0% × 15%
Action: Watch closely — could escalate to Attend.
EPSS PROB
1%
EPSS %ILE
60%
KEV
Not listed

Published

May 13, 2026

Last Modified

September 7, 2026

Advisory Details (5)

Auto-updated Sep 14, 2026
🔬 Proof of concept available. Patch available. Sources: github, redhat.
redhat Patch Available
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-43999.json
github Patch Available🟡 PoC Available

NodeVM builtin allowlist bypass via `module` builtin's `Module._load` allows sandbox escape · Advisory · patriksimek/vm2 · GitHub

https://github.com/patriksimek/vm2/security/advisories/GHSA-947f-4v7f-x2v8
redhat

2477196 – (CVE-2026-43999) CVE-2026-43999 vm2: vm2: Remote code execution via NodeVM builtin allowlist bypass

https://bugzilla.redhat.com/show_bug.cgi?id=2477196
redhat Patch Available

CVE-2026-43999 - Red Hat Customer Portal

Affected: Red Hat Enterprise Linux 8 or OpenShift Container Platform 4, is affected by this vulnerability and a fix may be released to a

https://access.redhat.com/security/cve/CVE-2026-43999
redhat Patch Available
https://access.redhat.com/errata/RHSA-2026:50850

Vendor Advisories for CVE-2026-43999(1)

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

Patch Availability(1)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatansible-automation-platform/automation-portal:17858542262026-08-05redhat

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)
npm(1)
PackageVulnerable rangeFixed inDependents
vm23.10.53.11.0—

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 6× in last 7d / 42× 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 208 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-43999?
CVE-2026-43999 is a critical vulnerability published on May 13, 2026. vm2 is an open source vm/sandbox for Node.js. Prior to 3.11.0, NodeVM's builtin allowlist can be bypassed when the module builtin is allowed (including via the '*' wildcard). The module builtin exposes Node's Module.load(), which loads any module by name directly in the host context, completely…
When was CVE-2026-43999 disclosed?
CVE-2026-43999 was first published in the National Vulnerability Database on May 13, 2026, with the most recent update on September 7, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-43999 actively exploited?
CVE-2026-43999 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 39.9% of all scored CVEs.
What is the CVSS score of CVE-2026-43999?
CVE-2026-43999 has a CVSS v3 base score of 9.9 (NVD).
How do I remediate CVE-2026-43999?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-43999, 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

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