CVE-2026-92954 vm2 3.10.0 through 3.11.7 Denial of Service via Host Promise
An attacker can crash the host Node.js process by ignoring rejected Promises returned from host functions within the vm2 sandbox.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-92954?
CVE-2026-92954 is a critical denial of service vulnerability in patriksimek vm2, published on 17 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
vm2 is a sandbox library for running untrusted JavaScript in Node.js. In versions >= 3.10.0 and <= 3.11.7, Promises returned from the host realm into the sandbox are not marked as handled at the bridge boundary; only Promises created inside the sandbox are wrapped with a rejection-swallowing handler (lib/setup-sandbox.js), and the bridge only installs host-side rejection sanitizers when sandbox code calls .then/.catch/.finally. As a result, code running in the sandbox can invoke a host function that returns a rejected Promise (for example events.once() exposed via the NodeVM events builtin, or any embedder-provided Promise-returning API) and simply ignore the return value, leaving the host Promise unhandled so that Node.js's default unhandled-rejection behavior terminates the host process. This is an incomplete fix of GHSA-hw58-p9xv-2mjh. The issue is fixed in version 3.11.8.
Weakness: CWE-248
Which versions are affected by CVE-2026-92954?
2 open source packages ship an affected version, including vm2.
| Package | Affected | Fixed in |
|---|---|---|
vm2 npm | From 3.10.0 | 3.11.8 |
vm2 npm | From 3.10.0 | 3.11.8 |
How do I fix CVE-2026-92954?
Upgrade vm2 to 3.11.8 or later.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-92954 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-92954 exists.
Sources
Also known as CLEANSTART-2026-IT25891, ECHO-0f0b-25d6-437d, GHSA-gjq8-xm47-88rc, MINI-2vxr-w6pw-qfv7, ROOT-APP-NPM-CVE-2026-92954.