CVE-2026-92954: vm2 (npm)

Should you act?

Critical and remotely reachable

No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

Not in CISA KEV, but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
EPSS 0.5%, percentile 41: FIRST’s model estimates a 0.5% chance of exploitation activity in the next 30 days, higher than 41% of all scored CVEs (low). EPSS is a probability, not a verdict.
Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
Only applies if your dependency tree includes vm2 (npm) >= 3.10.0, <= 3.11.7, fixed in 3.11.8. Check your lockfile, including transitive dependencies.
Editorial verdict: Check exposure. vm2: 22 Critical Sandbox Escapes, Fixed in 3.12.2 — If anything outside your trust boundary can get code into vm2, upgrade to 3.12.2 today and plan to move that code out of process; if vm2 only runs your own code, upgrade on a normal cycle.

What it is

vm2 is a sandbox library for running untrusted JavaScript in Node.js. In versions >= 3.10.0 and

From the GitHub advisory

Summary

vm2 current head (v3.11.5, commit 7a1f5100b96f48d34e0fe104ab37c0acc5944f92) can still be used to terminate the host Node.js process when sandbox code calls a host-realm function that returns a rejected host Promise and then ignores the returned value.

This is an incomplete-fix variant of the GHSA-hw58-p9xv-2mjh unhandled rejection hardening. The localPromise constructor now catches and consumes sandbox-created unhandled rejections, but host Promises returned across the bridge are not marked handled at the bridge boundary. If the sandbox does not attach .catch() or .then(..., onRejected), Node's default unhandled rejection behavior terminates the host process.

Technical Details

lib/setup-sandbox.js hardens sandbox-created Promises by wrapping the executor and attaching a benign swallow tail:

Weakness type: CWE-248, CWE-703.

Product: vm2 (npm) · Assigned by: VulnCheck · Published: 2026-09-17

Affected and fixed versions

Ecosystem	Package	Vulnerable	First fixed
npm	`vm2`	>= 3.10.0, <= 3.11.7	3.11.8

Vendor	Product	Affected versions (per CVE record)
patriksimek	vm2	3.10.0 < 3.11.8

Severity scores

Scored by	CVSS	Score	Vector
VulnCheck	4.0	9.2 Critical	`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H`
VulnCheck	3.1	8.6 High	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H`
GitHub	4.0	9.2	`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H`

Attack vector: network (remotely reachable)
Attack complexity: low
Attack requirements: none
Privileges required: none (no login)
User interaction: none

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
CISA SSVC assessment: exploitation poc, automatable yes, technical impact partial.
FIRST EPSS (model of 2026-10-21): 0.49% probability of exploitation activity in the next 30 days; percentile 41.

Timeline

2026-08-17 — erroneo.us brief: vm2: 22 Critical Sandbox Escapes, Fixed in 3.12.2
2026-09-17 — CVE record published by VulnCheck
2026-09-26 — CVE record last updated
2026-10-05 — GitHub-reviewed advisory GHSA-gjq8-xm47-88rc published (critical)

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.