What is CVE-2026-43997?

CVE-2026-43997 is a critical-severity vulnerability in Patriksimek Vm2, classified under Code Injection. CVSS score: 10.0/10. Published 2026-05-13.

How severe is CVE-2026-43997?

Critical severity. CVSS v3 base score is 10.0 out of 10.

RCE in Patriksimek Vm2

CVE-2026-43997

vm2 is an open source vm/sandbox for Node.js. Prior to 3.11.0, it is possible to obtain the host Object. There are various ways to use the host Object, to escape the sandbox, one example would be using HostObject.getOwnPropertySymbols to obtain Symbol(nodejs.util.inspect.custom). This vulnerability is fixed in 3.11.0.

Vulnerability class: RCE (Remote Code Execution)

Published 2026-05-13 · last modified 2026-09-07.

CVSS v3 metric

CVSS v3 base score 10.0 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.008 (54.7th percentile), scored 2026-10-19.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 55th percentile — 54.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.010 · newest: 0.008 · change: -0.002

Affected products

Patriksimek Vm2 — versions < 3.11.0
Vm2 Project

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-43997?: CVE-2026-43997 is a critical-severity vulnerability in Patriksimek Vm2, classified under Code Injection. CVSS score: 10.0/10. Published 2026-05-13.
How severe is CVE-2026-43997?: Critical severity. CVSS v3 base score is 10.0 out of 10.