CVE-2026-100721

CRITICALPre-NVD 9.010.0
EchelonGraph scoreMEDIUM confidence

“▲” beside the score: it is higher than the CVSS score beside it.

Score 10.0 from GitHub Security Advisory (severity: CRITICAL) published 2026-10-05. A secondary CVSS source baseline 9.0; sources differ by 1.0.

Triggered by: GitHub Security Advisory CVSS
Sources: EPSS, GitHub Security Advisory, a secondary CVSS source
Elevated

Also known asEUVD-2026-87858 (ENISA EUVD) · GHSA-5h3f-q97h-ccvc (GitHub Security Advisories) · GHSA-c9wr-qm7p-p6vc (GitHub Security Advisories)Source: ENISA EUVD

10.0EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines at low or medium mission impact and sooner than that at high (the SSVC decision on this page).
  • CISA's Vulnrichment rates exploitation as PoC; EchelonGraph holds no exploit-code reference for it
CISA-KEV: Not listedEPSS PROB: 0.6%CVSS: 9.0Exploit: No code on recordExposed services: Not assessed

A fix is available — apply it.

vm2 before 3.12.2 contains an authorization bypass in the NodeVM external-module resolver. When an embedder configures require.external with a custom resolver (and context: 'host'), LegacyResolver.customResolve in lib/resolver-compat.js records the resolved module directory in this.externals as new RegExp('^' + escapeRegExp(resolvedPath)), without requiring a path separator or end-of-string boundary. Untrusted guest code can therefore require the allowlisted module (e.g. foo) and then require the absolute path of a non-allowlisted sibling whose path merely shares the resolved prefix (e.g. .../node_modules/foo2/index.js); the sibling passes isPathAllowedForModule and is loaded through hostRequire, so its top-level code runs in the host process before the exports are wrapped with vm.readonly, resulting in a sandbox escape and arbitrary code execution in the host context.

CVSS v3
9.0
EG Score
10.0CRITICALmedium confidence
EG Risk
61
EG Risk 61/100

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)
Severity100% × 45%
Impact severity (EG Severity): CVSS 10.0 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation40% × 40%
EchelonGraph's fixed weight for EG-KEV Tier 3 (Elevated): a constant, not a probability.
Automatability0% × 15%
CISA's SSVC Automatable value: no (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low, Track* at medium and Attend at high mission impact.
Exploitation public PoC (CISA Vulnrichment) · Automatable no (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 within your standard update timelines at low or medium mission impact and sooner than that at high.
EPSS PROB
0.6%
EPSS %ILE
48th
KEV
Not listed

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

The EG score (10.0): severity, escalated by confirmed exploitation. This CVE's 10.0 is its impact severity (EG Severity), not escalated.

EG Severity
10.0 CRITICALCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
0.6% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-12). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Track* at medium mission impactTrack at low, Track* at medium and Attend at high mission impact.CISA BOD 26-04: 14 days if the affected system is publicly exposed; Fix on system upgrade 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)Track at low, Track* at medium and Attend at high mission impact.

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

Exploitation public PoC (CISA Vulnrichment) · Automatable no (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)14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.

The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (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

Published

September 27, 2026

Last Modified

September 28, 2026

Advisory Details (5)

Auto-updated Sep 27, 2026
Patch available. Sources: github, github_commit.
Web page

vm2 before 3.12.2 Authorization Bypass via Custom Resolver | Advisories | VulnCheck

https://www.vulncheck.com/advisories/vm2-before-3.12.2-authorization-bypass-via-custom-resolver
GitHub commit Patch Available

commit 91034466bfb7 (patriksimek/vm2)

Patch available: patriksimek/vm2 v3.12.0 (contains commit 91034466bfb7)

https://github.com/patriksimek/vm2/commit/91034466bfb7f56b95fd48083ec6ca36d058f164
GitHub commit Patch Available

commit ab4ee7d803e8 (patriksimek/vm2)

Patch available: patriksimek/vm2 v3.11.7 (contains commit ab4ee7d803e8)

https://github.com/patriksimek/vm2/commit/ab4ee7d803e8c80155e9eb3672226bddbca4aa9c
GitHub commit Patch Available

commit 6ac3916da84e (patriksimek/vm2)

Patch available: patriksimek/vm2 v3.11.7 (contains commit 6ac3916da84e)

https://github.com/patriksimek/vm2/commit/6ac3916da84e060c403e407b6b6318fcc66b0e72
GitHub advisoryMentions a patch (unverified)

NodeVM custom resolution bypasses external path boundaries · Advisory · patriksimek/vm2 · GitHub

https://github.com/patriksimek/vm2/security/advisories/GHSA-5h3f-q97h-ccvc

Vendor Advisories for CVE-2026-100721(2)

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

Patch Availability(2)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
redhatansible-automation-platform/bootc-automation-portal-rhel9:17926411022026-10-22redhat
npmvm2 @ 3.12.2 (fixes <= 3.12.1)—ghsa

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 rangeFix by version rangeDependents
vm2—
  • every version up to 3.12.2: fixed in 3.12.2
—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 21× in last 7d / 66× 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.

Showing the most recent 100 of 186 rows on record for this CVE.

A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. None are among the latest 100 rows. The 86 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-11-13 05:46 UTCEchelonGraph re-scored
  2. 2026-11-13 05:46 UTCVendor advisory
  3. 2026-11-13 05:46 UTCGHSA enrichmentGHSA-5h3f-q97h-ccvc · GitHub severity CRITICAL · GitHub CVSS 10.0
  4. 2026-11-12 16:32 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  5. 2026-11-12 04:59 UTCEchelonGraph re-scored
  6. 2026-11-12 04:59 UTCVendor advisory
  7. 2026-11-12 04:59 UTCGHSA enrichmentGHSA-5h3f-q97h-ccvc · GitHub severity CRITICAL · GitHub CVSS 10.0
  8. 2026-11-11 16:37 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  9. 2026-11-11 04:12 UTCEchelonGraph re-scored
  10. 2026-11-11 04:12 UTCVendor advisory
  11. 2026-11-11 04:12 UTCGHSA enrichmentGHSA-5h3f-q97h-ccvc · GitHub severity CRITICAL · GitHub CVSS 10.0
  12. 2026-11-10 16:41 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  13. 2026-11-10 03:21 UTCEchelonGraph re-scored
  14. 2026-11-10 03:21 UTCVendor advisory
  15. 2026-11-10 03:21 UTCGHSA enrichmentGHSA-5h3f-q97h-ccvc · GitHub severity CRITICAL · GitHub CVSS 10.0
  16. 2026-11-09 16:33 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  17. 2026-11-09 02:34 UTCEchelonGraph re-scored
  18. 2026-11-09 02:34 UTCVendor advisory
  19. 2026-11-09 02:34 UTCGHSA enrichmentGHSA-5h3f-q97h-ccvc · GitHub severity CRITICAL · GitHub CVSS 10.0
  20. 2026-11-08 16:37 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  21. 2026-11-08 01:47 UTCEchelonGraph re-scored
  22. 2026-11-08 01:47 UTCVendor advisory
  23. 2026-11-08 01:47 UTCGHSA enrichmentGHSA-5h3f-q97h-ccvc · GitHub severity CRITICAL · GitHub CVSS 10.0
  24. 2026-11-07 16:37 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  25. 2026-11-07 01:00 UTCEchelonGraph re-scored
Show 75 more
  1. 2026-11-07 01:00 UTCVendor advisory
  2. 2026-11-07 01:00 UTCGHSA enrichmentGHSA-5h3f-q97h-ccvc · GitHub severity CRITICAL · GitHub CVSS 10.0
  3. 2026-11-06 16:35 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  4. 2026-11-06 00:13 UTCEchelonGraph re-scored
  5. 2026-11-06 00:13 UTCVendor advisory
  6. 2026-11-06 00:13 UTCGHSA enrichmentGHSA-5h3f-q97h-ccvc · GitHub severity CRITICAL · GitHub CVSS 10.0
  7. 2026-11-05 21:25 UTCOSV refresh
  8. 2026-11-05 16:36 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  9. 2026-11-04 23:26 UTCEchelonGraph re-scored
  10. 2026-11-04 23:26 UTCVendor advisory
  11. 2026-11-04 23:26 UTCGHSA enrichmentGHSA-5h3f-q97h-ccvc · GitHub severity CRITICAL · GitHub CVSS 10.0
  12. 2026-11-04 16:34 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  13. 2026-11-04 09:59 UTCEchelonGraph re-scored
  14. 2026-11-04 09:59 UTCVendor advisory
  15. 2026-11-04 09:59 UTCGHSA enrichmentGHSA-5h3f-q97h-ccvc · GitHub severity CRITICAL · GitHub CVSS 10.0
  16. 2026-11-03 16:45 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  17. 2026-11-03 09:11 UTCEchelonGraph re-scored
  18. 2026-11-03 09:11 UTCVendor advisory
  19. 2026-11-03 09:11 UTCGHSA enrichmentGHSA-5h3f-q97h-ccvc · GitHub severity CRITICAL · GitHub CVSS 10.0
  20. 2026-11-02 16:43 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  21. 2026-11-02 08:24 UTCEchelonGraph re-scored
  22. 2026-11-02 08:24 UTCVendor advisory
  23. 2026-11-02 08:24 UTCGHSA enrichmentGHSA-5h3f-q97h-ccvc · GitHub severity CRITICAL · GitHub CVSS 10.0
  24. 2026-11-01 16:33 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  25. 2026-11-01 07:38 UTCEchelonGraph re-scored▲ 1.00
  26. 2026-11-01 07:38 UTCVendor advisory
  27. 2026-11-01 07:38 UTCGHSA enrichmentGHSA-5h3f-q97h-ccvc · GitHub severity CRITICAL · GitHub CVSS 10.0
  28. 2026-10-31 16:31 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  29. 2026-10-31 06:50 UTCEchelonGraph re-scored
  30. 2026-10-31 06:50 UTCVendor advisory
  31. 2026-10-30 16:33 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  32. 2026-10-30 06:01 UTCEchelonGraph re-scored
  33. 2026-10-30 06:01 UTCVendor advisory
  34. 2026-10-29 16:32 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  35. 2026-10-29 05:14 UTCEchelonGraph re-scored
  36. 2026-10-29 05:14 UTCVendor advisory
  37. 2026-10-28 16:31 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  38. 2026-10-28 04:26 UTCEchelonGraph re-scored
  39. 2026-10-28 04:26 UTCVendor advisory
  40. 2026-10-27 16:31 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  41. 2026-10-27 03:32 UTCEchelonGraph re-scored
  42. 2026-10-27 03:32 UTCVendor advisory
  43. 2026-10-26 20:24 UTCEchelonGraph re-scored
  44. 2026-10-26 20:24 UTCVendor advisory
  45. 2026-10-26 16:30 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  46. 2026-10-25 17:53 UTCEchelonGraph re-scored
  47. 2026-10-25 17:53 UTCVendor advisory
  48. 2026-10-25 16:32 UTCEPSS rescoreEPSS 0.6% · 47th percentile
  49. 2026-10-25 15:58 UTCEchelonGraph re-scored
  50. 2026-10-24 16:33 UTCEchelonGraph re-scored
  51. 2026-10-24 16:33 UTCVendor advisory
  52. 2026-10-24 16:31 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  53. 2026-10-23 16:31 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  54. 2026-10-23 15:45 UTCEchelonGraph re-scored
  55. 2026-10-23 15:45 UTCVendor advisory
  56. 2026-10-22 16:33 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  57. 2026-10-22 14:56 UTCEchelonGraph re-scored
  58. 2026-10-21 16:31 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  59. 2026-10-21 14:07 UTCEchelonGraph re-scored
  60. 2026-10-20 16:31 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  61. 2026-10-20 13:06 UTCEchelonGraph re-scored
  62. 2026-10-19 16:31 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  63. 2026-10-19 12:15 UTCEchelonGraph re-scored
  64. 2026-10-18 16:31 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  65. 2026-10-18 05:11 UTCEchelonGraph re-scored
  66. 2026-10-17 16:33 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  67. 2026-10-17 08:58 UTCEchelonGraph re-scored
  68. 2026-10-16 16:40 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  69. 2026-10-16 08:08 UTCEchelonGraph re-scored
  70. 2026-10-15 16:31 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  71. 2026-10-15 07:11 UTCEchelonGraph re-scored
  72. 2026-10-14 16:31 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  73. 2026-10-14 03:07 UTCEchelonGraph re-scored
  74. 2026-10-13 16:33 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  75. 2026-10-12 16:41 UTCEchelonGraph re-scored

Frequently asked(5)

What is CVE-2026-100721?
CVE-2026-100721 is a critical-severity vulnerability; its CVE record was published on September 27, 2026. vm2 before 3.12.2 contains an authorization bypass in the NodeVM external-module resolver. When an embedder configures require.external with a custom resolver (and context: 'host'), LegacyResolver.customResolve in lib/resolver-compat.js records the resolved module directory in this.externals as new…
When was CVE-2026-100721 made public?
CVE-2026-100721 was made public on September 8, 2026: that is the date its CVE record's CNA, VulnCheck, gives for when the vulnerability was made public. The CVE record itself was published on September 27, 2026. EchelonGraph's copy of the record carries a last-modified date of September 28, 2026; the record at its source may have been updated since.
Is CVE-2026-100721 actively exploited?
CVE-2026-100721 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.6% probability of exploitation in the next 30 days (48th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-100721?
CVE-2026-100721 has a CVSS base score of 9.0 (a secondary CVSS source that NVD displays; NVD's own analysis pending). EchelonGraph synthesises a secondary CVSS source + FIRST EPSS + GHSA into a combined EG score of 10.0 (CRITICAL).
How do I remediate CVE-2026-100721?
A fix for CVE-2026-100721 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-100721 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-100721

Explore →

Is Your Infrastructure Affected by CVE-2026-100721?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.