Security Digest · Vulnerability record
CVE-2026-47131: vm2 has a Sandbox Escape issue
vm2 is an open source vm/sandbox for Node.js.
CVSS 10.0 Critical EPSS 0.6% · p50
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 0.6%, percentile 50: FIRST’s model estimates a 0.6% chance of exploitation activity in the next 30 days, higher than 50% of all scored CVEs (moderate). 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) <= 3.11.3, fixed in 3.11.4. Check your lockfile, including transitive dependencies.
What it is
vm2 is an open source vm/sandbox for Node.js. Prior to version 3.11.4, by combining Buffer.call.call({}.lookupGetter, Buffer, "proto"), Buffer.call.call({}.lookupSetter, Buffer, "proto"), and Node.js's ERRINVALIDARGTYPE Error, the host's TypeError constructor can be obtained, which allows the escape from the sandbox. This allows attackers to run arbitrary code. This issue has been patched in version 3.11.4.
From the GitHub advisory
Summary By combining Buffer.call.call({}.lookupGetter, Buffer, "proto"), Buffer.call.call({}.lookupSetter, Buffer, "proto"), and Node.js's ERRINVALIDARGTYPE Error, the host's TypeError constructor can be obtained, which allows the escape from the sandbox. This allows attackers to run arbitrary code.
PoC
Impact Sandbox Escape → RCE
Weakness type: CWE-913.
Product: vm2 (npm) · Assigned by: GitHub_M · Published: 2026-06-12
Affected and fixed versions
| Ecosystem | Package | Vulnerable | First fixed |
|---|---|---|---|
| npm | vm2 | <= 3.11.3 | 3.11.4 |
| Vendor | Product | Affected versions (per CVE record) |
|---|---|---|
| patriksimek | vm2 | < 3.11.4 |
Severity scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_M | 3.1 | 10 Critical | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H |
| GitHub | 3.1 | 10.0 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H |
- Attack vector: network (remotely reachable)
- Attack complexity: low
- Privileges required: none (no login)
- User interaction: none
- Scope: changed (can affect other components)
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 total.
- FIRST EPSS (model of 2026-10-21): 0.65% probability of exploitation activity in the next 30 days; percentile 50.
Timeline
- — GitHub-reviewed advisory GHSA-v6mx-mf47-r5wg published (critical)
- — CVE record published by GitHub_M
- — CVE record last updated
Sources and references
Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.
Vulnerability records
- GitHub Advisory GHSA-v6mx-mf47-r5wg github.com
- CVE.org record CVE-2026-47131 cve.org
- NVD entry CVE-2026-47131 nvd.nist.gov
Other references from the CVE record and advisory
- github.com github.com
- github.com github.com
- github.com github.com