CVE-2026-92936: Vm2 Vm2 Leaks Absolute Host Filesystem Vulnerability

MODERATE
Advisory Identifier: GHSA-x6m4-chr9-cg97
CVSS 5.8
CWE-209 CWE-497
Published
Advisory Summary

CVE-2026-92936 is a MODERATE (CVSS 5.8) vm2 leaks absolute host filesystem vulnerability (CWE-209: Generation of Error Message Containing Sensitive Information) affecting Vm2 libraries in the npm ecosystem. The issue involves vm2 leaks absolute host filesystem paths to sandbox code via error stack formatting. Remediation is available by upgrading affected packages to version 3.11.7.

CVE-2026-92936 at a Glance

CVE Identifier CVE-2026-92936
GHSA Identifier GHSA-x6m4-chr9-cg97
Severity MODERATE
CVSS v3.1 Base Score 5.8
CWE Classification CWE-209: Generation of Error Message Containing Sensitive Information
Affected Product Vm2
Package Ecosystem npm
Published Date
Last Updated

Security Impact

CVSS: 5.8

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Changed (S:C)
Confidentiality Low (C:L)
Integrity None (I:N)
Availability None (A:N)

How to Fix CVE-2026-92936

To remediate this vulnerability, upgrade all affected Vm2 dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

vm2 fixed: 3.11.7
npm install vm2@3.11.7
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release:

npm ls vm2

How to Check if You Are Affected

To determine whether your Node.js application is affected by CVE-2026-92936, inspect your project dependencies using npm:

npm ls vm2

Analyze the terminal output to locate any version of Vm2 in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 3.11.7), your application is affected.

Note: The npm ls vm2 command inspects dependencies declared in your package.json and lockfile; it does not perform automated runtime dynamic scanning.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-209: Generation of Error Message Containing Sensitive Information, where the product generates an error message that includes sensitive information about its environment, users, or associated data. In Vm2, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

## Summary Attacker-controlled code can trigger a host-realm syntax error and read its stack through the vm2 bridge. Host-realm stack formatting bypasses the sandbox-side redaction, so the returned value exposes absolute paths from vm2, Node.js internals, and the embedding application. Default VM and NodeVM configurations are affected without requiring special options. ## PoC A default-configured `VM` runs attacker-supplied code. Calling `eval` with deliberately malformed source makes the host-side source transformer throw a `SyntaxError`; reading `.stack` on the caught error exposes the host call stack to the sandbox. ```js const { VM } = require("vm2"); console.log(new VM().run(` var s; try { eval("@@@ catch") } catch (e) { s = e.stack } s; `)); ``` ### Observed output ```text SyntaxError: Unexpected character '@' at makeNiceSyntaxError (.../lib/transformer.js:41:16) at transformer (.../lib/transformer.js:116:8) at Object.transformAndCheck (.../lib/vm.js:76:14) at Object.apply (.../lib/setup-sandbox.js:2585:16) at VM.run (.../lib/vm.js:529:16) ``` The stack string returned to the sandbox contains absolute host paths for `lib/transformer.js`, `lib/vm.js`, `lib/setup-sandbox.js`, Node internals, and the embedding application's own source file. ## Impact Sandboxed code running under the default `new VM()` or `new NodeVM()` configuration can read absolute filesystem paths of the embedding application's source tree plus host function names, bypassing the host-path redaction added for GHSA-v27g-jcqj-v8rw. On a multi-tenant code-runner this discloses deployment layout such as `/home/app/...` or `/var/task/...`, useful for fingerprinting and for chaining into further attacks. The bridge forwards `.stack` reads to the host-realm formatter (`lib/bridge.js:1482`), so the sandbox-side stack redaction never runs; the leak does not require special configuration and persists when string eval is disabled, because the host-side transformer throws before eval is handled. Information disclosure only, no code execution.

CVE-2026-92936 Affected Vm2 Versions

1 component(s)
Fixed Versions:
3.11.7
Product / Package Ecosystem Affected Versions Fixed Version
vm2
npm
≥ 3.11.0
< 3.11.7
3.11.7

References

Frequently Asked Questions

What is CVE-2026-92936?
CVE-2026-92936 is a security vulnerability in Vm2 involving vm2 leaks absolute host filesystem paths to sandbox code via error stack formatting under CWE-209: Generation of Error Message Containing Sensitive Information.
Which Vm2 versions are affected?
Affected versions include releases prior to 3.11.7 across affected packages: vm2.
What version fixes CVE-2026-92936?
Upgrading to 3.11.7 (or the latest patched release for your respective branch) resolves the vulnerability.
Is vm2 affected?
Yes, vm2 is affected in releases prior to 3.11.7. Upgrade your dependency to 3.11.7 or later.
What is the CVSS score of CVE-2026-92936?
CVE-2026-92936 has a CVSS v3.1 base score of 5.8 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N.
What CWE is associated with CVE-2026-92936?
CVE-2026-92936 is classified under CWE-209: Generation of Error Message Containing Sensitive Information (The product generates an error message that includes sensitive information about its environment, users, or associated data.).
How can I check npm dependencies for CVE-2026-92936?
Run the dependency tree command: 'npm ls vm2'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-x6m4-chr9-cg97",
  "modified" : "2026-10-05T22:35:32Z",
  "published" : "2026-10-05T22:35:31Z",
  "aliases" : [ "CVE-2026-92936" ],
  "summary" : "vm2 leaks absolute host filesystem paths to sandbox code via error stack formatting",
  "details" : "## Summary\n\nAttacker-controlled code can trigger a host-realm syntax error and read its stack through the vm2 bridge. Host-realm stack formatting bypasses the sandbox-side redaction, so the returned value exposes absolute paths from vm2, Node.js internals, and the embedding application. Default VM and NodeVM configurations are affected without requiring special options.\n\n## PoC\n\nA default-configured `VM` runs attacker-supplied code. Calling `eval` with deliberately malformed source makes the host-side source transformer throw a `SyntaxError`; reading `.stack` on the caught error exposes the host call stack to the sandbox.\n\n```js\nconst { VM } = require(\"vm2\");\nconsole.log(new VM().run(`\n  var s; try { eval(\"@@@ catch\") } catch (e) { s = e.stack }\n  s;\n`));\n```\n\n### Observed output\n\n```text\nSyntaxError: Unexpected character '@'\n    at makeNiceSyntaxError (.../lib/transformer.js:41:16)\n    at transformer (.../lib/transformer.js:116:8)\n    at Object.transformAndCheck (.../lib/vm.js:76:14)\n    at Object.apply (.../lib/setup-sandbox.js:2585:16)\n    at VM.run (.../lib/vm.js:529:16)\n```\n\nThe stack string returned to the sandbox contains absolute host paths for `lib/transformer.js`, `lib/vm.js`, `lib/setup-sandbox.js`, Node internals, and the embedding application's own source file.\n\n## Impact\n\nSandboxed code running under the default `new VM()` or `new NodeVM()` configuration can read absolute filesystem paths of the embedding application's source tree plus host function names, bypassing the host-path redaction added for GHSA-v27g-jcqj-v8rw. On a multi-tenant code-runner this discloses deployment layout such as `/home/app/...` or `/var/task/...`, useful for fingerprinting and for chaining into further attacks. The bridge forwards `.stack` reads to the host-realm formatter (`lib/bridge.js:1482`), so the sandbox-side stack redaction never runs; the leak does not require special configuration and persists when string eval is disabled, because the host-side transformer throws before eval is handled. Information disclosure only, no code execution.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N"
  }, {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:L/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "vm2"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "3.11.0"
      }, {
        "fixed" : "3.11.7"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 3.11.6"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/patriksimek/vm2/security/advisories/GHSA-x6m4-chr9-cg97"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-92936"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/patriksimek/vm2/commit/5d5ba5343af571c688a3a81cefad2de25b94180a"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/patriksimek/vm2"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/patriksimek/vm2/releases/tag/v3.11.7"
  }, {
    "type" : "WEB",
    "url" : "https://www.vulncheck.com/advisories/vm2-3.11.0-before-3.11.7-information-disclosure-via-error-stack"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-209", "CWE-497" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-10-05T22:35:31Z",
    "nvd_published_at" : null
  }
}