{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 3.11.3"
      },
      "package": {
        "ecosystem": "npm",
        "name": "vm2"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.11.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-47141"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-668"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-05-29T18:20:45Z",
    "nvd_published_at": "2026-06-12T15:16:28Z",
    "severity": "MODERATE"
  },
  "details": "## Summary\n\n`NodeVM` exposes some process-wide observability builtins when they are allowed through `require.builtin`.\n\nThe following builtins are not blocked by the dangerous builtin denylist:\n\n```text\ndiagnostics_channel\nasync_hooks\nperf_hooks\n```\n\nThese modules are process-wide, not sandbox-local. Sandboxed code can use them to observe host application data across the vm2 boundary.\n\n**Note**: It is a host data exposure issue. The impact depends on whether the host application allows these builtins and uses HTTP, async request context, diagnostics channels, or performance marks in the same process.\n\n## Details\n\nNon-denied builtins are exposed to the sandbox through `lib/builtin.js`:\n\n```js\nbuiltins.set(key, special ? special : vm =\u003e vm.readonly(hostRequire(key)));\n```\n\n`diagnostics_channel`, `async_hooks`, and `perf_hooks` are not denied. These modules expose host process state rather than sandbox-local state.\n\nConfirmed examples:\n\n1. `diagnostics_channel` lets sandboxed code subscribe to Node.js HTTP diagnostic channels such as `http.server.request.start`. The sandbox receives host HTTP request objects and can read headers such as `Authorization` or session tokens.\n2. `async_hooks.executionAsyncResource()` lets sandboxed code read the current host `AsyncResource`. If the host stores request/user data on that resource, the sandbox can read it.\n3. `perf_hooks.performance.getEntriesByType(\u0027mark\u0027)` lets sandboxed code read host performance timeline entries.\n\n## PoC\n\nRun from the vm2 repository root:\n\n```bash\nnode poc/observability-builtins-info-leak.js\n```\n[observability-builtins-info-leak.js](https://github.com/user-attachments/files/27571259/observability-builtins-info-leak.js)\n\nThe PoC uses only the specific builtin being tested in each section.\n\nIt confirms:\n\n```text\ndiagnostics_channel: sandbox reads host HTTP request headers\nasync_hooks: sandbox reads host AsyncResource data\nperf_hooks: sandbox reads host performance mark names\n```\n\nExample impact from the PoC:\n\n```text\nauthorization: Bearer HOST_HTTP_SECRET_...\nx-session-token: HOST_HTTP_SECRET_...\n```\n\nThese values are sent to a host HTTP server, but the sandbox reads them through `diagnostics_channel`.\n\n\u003cimg width=\"997\" height=\"566\" alt=\"Screenshot 2026-05-10 at 1 13 20\u202fPM\" src=\"https://github.com/user-attachments/assets/36a7d600-8b53-4bfe-ab06-4e6dcfad5015\" /\u003e\n\n## Impact\n\nAn attacker who can run untrusted JavaScript inside `NodeVM` with affected builtin settings can observe data from the host process.\n\nIn a real application, this may expose HTTP request headers, authorization tokens, session tokens, request context values, user identifiers, or other sensitive diagnostics data from the host application or from other users.\n\n## Suggested fix\n\nTreat process-wide observability modules as dangerous builtins for untrusted sandboxes.\n\nAt minimum, consider blocking:\n\n```text\ndiagnostics_channel\nasync_hooks\nperf_hooks\n```\n\nThese modules are not sandbox-local and can expose host process state across the vm2 boundary.",
  "id": "GHSA-9g8x-92q2-p28f",
  "modified": "2026-06-12T19:30:13Z",
  "published": "2026-05-29T18:20:45Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/patriksimek/vm2/security/advisories/GHSA-9g8x-92q2-p28f"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-47141"
    },
    {
      "type": "WEB",
      "url": "https://github.com/patriksimek/vm2/commit/e1c48fce05189f48e71efbd32af0754efa4066bb"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/patriksimek/vm2"
    },
    {
      "type": "WEB",
      "url": "https://github.com/patriksimek/vm2/releases/tag/v3.11.4"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:L/SI:N/SA:N/E:U",
      "type": "CVSS_V4"
    }
  ],
  "summary": "NodeVM observability builtins leak host process and HTTP request data"
}