The vm2 NodeVM module's builtin: ['*'] configuration expands to include the 'os' and 'dns' Node.js built-in modules, which expose host process state that cannot be contained by the vm2 sandbox boundary. The 'os' module exposes sensitive host information such as user identity and network topology, while the 'dns' module includes write APIs like dns.setServers() that allow sandboxed code to hijack the host's DNS resolution process. This leads to a critical vulnerability with high confidentiality and integrity impact, as sandboxed code can both read sensitive host data and perform process-wide DNS hijacking without requiring privileges. The issue is related to but distinct from a previously fixed class of process-wide observability builtins. The fix involves adding 'os' and 'dns' to the dangerous builtins set, preventing their inclusion when using the '*' wildcard in builtin allowlists.

An attacker controlling sandboxed code in vm2 with builtin: ['*'] can read sensitive host process information including user identity, network interfaces, and host telemetry, violating confidentiality. They can also perform process-wide DNS hijacking by calling dns.setServers(), affecting all DNS lookups made by the host process and potentially redirecting network traffic. This compromises both confidentiality and integrity of the host environment. No privileges are required for exploitation as the attacker controls the sandbox code, making the impact critical.

A patch is available that adds 'os' and 'dns' to the dangerous builtins list in vm2, preventing their exposure when using the builtin: ['*'] configuration. Users should upgrade to vm2 version 3.11.6 or later. Alternatively, manual exclusion of 'os' and 'dns' from the builtin allowlist is recommended if upgrading is not immediately possible. This mitigates the risk by preventing sandboxed code from accessing these modules and performing process-wide state reads or writes.