CVE-2026-92936: vm2 3.11.0 before 3.11.7 Information Disclosure via Error Stack
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.
Other sources
vm2 versions 3.11.0 through 3.11.6 leak absolute host filesystem paths to sandboxed code through error stack formatting. Attacker-supplied code can force the host-realm source transformer to throw a SyntaxError (for example by calling eval with malformed source) and then read the error's .stack property; the bridge forwards the .stack read to the host-realm formatter, bypassing the sandbox-side host-path redaction introduced for GHSA-v27g-jcqj-v8rw. The returned stack string discloses absolute paths from vm2, Node.js internals, and the embedding application's own source tree, along with host function names. Default new VM() and new NodeVM() configurations are affected without any special options, and the issue persists when string eval is disabled because the host-side transformer throws before eval is handled. The impact is information disclosure only; no code execution results. Fixed in vm2 3.11.7.
— MITRE
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
npm/vm2to a version that resolves this vulnerability.Fixed in 3.11.7 - Upgrade
Upgrade
vm2to a version that resolves this vulnerability.Fixed in 3.11.7
Event History
Frequently Asked Questions
Which deployments are affected?
Default new VM() and new NodeVM() configurations are affected in vm2 versions 3.11.0 through 3.11.6. No special options are required.
What must an attacker be able to do to disclose paths?
An attacker must be able to supply code that runs in the vm2 sandbox. They can trigger a host-realm SyntaxError, such as through eval with malformed source, and read the error's .stack property.
Does disabling string eval prevent this disclosure?
No. The host-side source transformer throws before eval is handled, so the issue persists when string eval is disabled.
What information can be exposed?
The returned stack string can disclose absolute paths from vm2, Node.js internals, and the embedding application's source tree, as well as host function names. The reported impact is information disclosure only, not code execution.
What version fixes the issue?
Upgrade vm2 to version 3.11.7, which fixes this issue.