vm2 is a widely used Node.js virtual machine sandbox. A flaw in the handling of Promises in versions prior to 3.10.5 allows an attacker to inject code that bypasses the sandbox boundary. The vulnerability is based on improper code generation (CWE‑94), security misconfiguration (CWE‑693) and improper use of Promise species (CWE‑807). When exploited, the attacker can break out of the isolated VM and execute arbitrary commands on the host system, leading to full system compromise.

The affected product is patriksimek’s vm2 library, versions earlier than 3.10.5. Users of any Node.js application that relies on vm2 for sandboxing—such as web servers, code execution services, or build tools—must ensure they are running at least version 3.10.5 or later. The advisory provides release notes for v3.10.5 as the fix.

An estimated CVSS score of 9.8 categorizes this as critical, with a high potential for exploitation. The EPSS score of < 1% indicates a very low probability that the vulnerability will be exploited in the wild, though the flaw remains a serious risk if an attacker can execute code within the vm2 sandbox. The vulnerability is not listed in the CISA KEV catalog, indicating no known mass exploitation. Nonetheless, the attack vector is inferred to be compromised or malicious sandboxed code—an attacker who can influence the content passed to vm2 poses a substantial threat. The only known mitigation is to apply the patch released in v3.10.5, after which the sandbox boundary is restored and the code execution vector is closed.