CVE-2026-92960

vm2 before 3.11.6 fails to restrict access to os and dns builtins under the builtin: ['*'] configuration, allowing sandbox code to read host process identity and network topology. Attackers can invoke dns.setServers() to hijack the host process DNS resolver globally, redirecting all subsequent host DNS queries through an attacker-controlled resolver.

vm2 before 3.11.6 fails to restrict access to os and dns builtins under the builtin: ['*'] configuration, allowing sandbox code to read host process identity and network topology. Attackers can invoke dns.setServers() to hijack the host process DNS resolver globally, redirecting all subsequent host DNS queries through an attacker-controlled resolver.

NodeVM builtin: ['*'] exposes os and dns — process-wide observability reads AND writes that hijack the host (sibling class of GHSA-9g8x-92q2-p28f)

CWE: CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor) chained with CWE-732 (Incorrect Permission Assignment for Critical Resource) and CWE-285 (Improper Authorization) — same class the maintainer codified as Defense Invariant #13 in lib/builtin.js and as Category 35 / GHSA-9g8x in docs/ATTACKS.md.

CVSS v3.1: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:L → 9.3 (Critical)

(Scope = Changed because the data being read and the state being written both belong to the host process, not the sandbox. Confidentiality = High because os.userInfo() returns host UID/GID/username/homedir + os.networkInterfaces() returns the full host network topology including container/VM interfaces with IPs and MAC addresses. Integrity = High because dns.setServers() is a process-wide write that hijacks every subsequent DNS lookup the host makes — including outbound HTTP, telemetry, npm/registry, and any host code that uses fetch or URL-based fs paths. Privileges Required = None because the attacker controls sandbox code, which is the threat model NodeVM exists to mitigate.)

Summary

GHSA-9g8x-92q2-p28f closed the "process-wide observability builtins" class by adding diagnostics_channel, async_hooks, perf_hooks, and v8 to DANGEROUS_BUILTINS in lib/builtin.js. The fix's rationale (in the commit message and docs/ATTACKS.md Category 35) is general:

Process-wide observability builtins. Unlike most Node builtins, these expose state of the entire host process rather than sandbox-local state — the vm2 boundary cannot usefully contain them because the data they surface […] belongs to the embedder. Even a readonly proxy that forwards every call to the host module is a working host-data exfiltration primitive.

Two builtins satisfying the same description were not added: os and dns. Both are reachable today under the documented builtin: ['*'] configuration; both expose host-process state that the vm.readonly() proxy cannot localise; and both have write APIs that mutate global host-process state from the sandbox (os.setPriority(), dns.setServers(), dns.setDefaultResultOrder()). dns.setServers() in particular turns sandbox code into a process-wide DNS hijack primitive — strictly worse than every read-only leak that GHSA-9g8x added.

Adding os and dns to DANGEROUS_BUILTINS extends the same fix to the rest of the class. The existing isDangerousBuiltin(key) family-prefix matcher (added by GHSA-rp36-8xq3-r6c4) automatically catches node:os, node:dns, and node:dns/promises once the family names are present.

Affected

• vm2 v3.11.5 (current package.json version on main) and the unreleased [3.11.4] slot that ships GHSA-9g8x-92q2-p28f, GHSA-rp36-8xq3-r6c4, GHSA-r9pm-gxmw-wv6p, et al.
• All NodeVM configurations that expand the builtin allowlist via '*' (the documented "full builtins" pattern) and have not manually appended -os, -dns exclusions — which is the recommended config in README and the test fixtures.
• Reproduced on Node v22.12.0 with HEAD 7a1f510 of the audit checkout.

Vulnerability details

[A] — Source: the '*' wildcard expansion includes os and dns

lib/builtin.js:166-167:

const BUILTIN_MODULES = (nmod.builtinModules || Object.getOwnPropertyNames(process.binding('natives')))
    .filter(s => !s.startsWith('internal/') && !s.startsWith('_') && !isDangerousBuiltin(s));

isDangerousBuiltin resolves the current DANGEROUS_BUILTINS set (lib/builtin.js:83-139):

const DANGEROUS_BUILTINS = new Set([
    'module', 'worker_threads', 'cluster', 'vm', 'repl', 'inspector', 'process',
    'trace_events', 'wasi',
    // GHSA-9g8x-92q2-p28f:
    'diagnostics_channel', 'async_hooks', 'perf_hooks', 'v8'
]);

os and dns are absent. Under…

vm2 before 3.11.6 fails to restrict access to os and dns builtins under the builtin: ['*'] configuration, allowing sandbox code to read host process identity and network topology. Attackers can invoke dns.setServers() to hijack the host process DNS resolver globally, redirecting all subsequent host DNS queries through an attacker-controlled resolver.

vm2 before 3.11.6 fails to restrict access to os and dns builtins under the builtin: ['*'] configuration, allowing sandbox code to read host process identity and network topology. Attackers can invoke dns.setServers() to hijack the host process DNS resolver globally, redirecting all subsequent host DNS queries through an attacker-controlled resolver.

vm2 before 3.11.6 fails to restrict access to os and dns builtins under the builtin: ['*'] configuration, allowing sandbox code to read host process identity and network topology. Attackers can invoke dns.setServers() to hijack the host process DNS resolver globally, redirecting all subsequent host DNS queries through an attacker-controlled resolver.