CVE-2026-100721 (GCVE-0-2026-100721)

Vulnerability from cvelistv5 – Published: 2026-09-27 01:28 – Updated: 2026-09-27 01:28
VLAI
Title
vm2 before 3.12.2 Authorization Bypass via Custom Resolver
Summary
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.
Severity
9.5 (Critical)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
9 (Critical)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
CWE
  • CWE-863 - Incorrect Authorization
Assigner
References
Impacted products
Vendor Product Version CPE status
patriksimek vm2 Affected: 0 , < 3.12.2 (semver)
Unaffected: 3.12.2 (semver)
guessed Create a notification for this product.
Date Public
2026-09-08 00:00
Credits
rexpository
Show details on NVD website
To clipboard 

{
  "containers": {
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      "affected": [
        {
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          "packageURL": "pkg:npm/vm2",
          "product": "vm2",
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              "status": "affected",
              "version": "0",
              "versionType": "semver"
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              "version": "3.12.2",
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        }
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        },
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          "url": "https://github.com/patriksimek/vm2/commit/91034466bfb7f56b95fd48083ec6ca36d058f164"
        },
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    "cveId": "CVE-2026-100721",
    "datePublished": "2026-09-27T01:28:28.596Z",
    "dateReserved": "2026-09-26T02:40:56.226Z",
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    "state": "PUBLISHED"
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                "product": "vm2",
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        "lastModified": "2026-09-27T02:17:18.070",
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                "modifiedPrivilegesRequired": "NOT_DEFINED",
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                "modifiedSubConfidentialityImpact": "NOT_DEFINED",
                "modifiedSubIntegrityImpact": "NOT_DEFINED",
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                "modifiedVulnIntegrityImpact": "NOT_DEFINED",
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}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.