[ CVE-2026-92958 · Published 17 Sep 2026 ]
vm2: NodeVM builtin denylist bypass via fs/promises despite -fs, allowing host filesystem writes
[ Why it matters ]Priority signals
- Public proof-of-concept exploit exists (CISA SSVC)
[ Description ]Official description
vm2 through 3.11.6 contains a builtin-module denylist bypass in NodeVM. When the embedder uses the builtin wildcard together with negative entries (e.g. require: { builtin: ['*', '-fs', '-child_process'] }), negative entries are matched by exact module name in lib/builtin.js, so -fs removes only the builtin named fs and does not remove builtin subpaths such as fs/promises. Sandboxed code can therefore call require('fs/promises') or require('node:fs/promises') and reach the promise-based filesystem API despite fs being denied; node: prefix handling is likewise inconsistent (a -node:fs/promises entry does not block require('fs/promises')). Host file creation and writing were confirmed via fsp.writeFile(), and other fs/promises operations (cp, mkdir, rename, rm, rmdir, truncate, read operations, etc.) are also reachable. This issue is fixed in vm2 3.11.7.
[ Fixes ]Fixes and patches
- vm2 3.11.7Fixed version · GitHub Advisories · npm package vm2: upgrade to 3.11.7 or later (affected <= 3.11.6)
[ Packages ]Affected open-source packages
- vm2 npmAffected <= 3.11.6 · fixed in 3.11.7 · GHSA-6rh5-qq4q-97xh