Bug 2536039 (CVE-2026-92958) - CVE-2026-92958 vm2: vm2: Sandbox escape via denylist bypass in NodeVM
Summary: CVE-2026-92958 vm2: vm2: Sandbox escape via denylist bypass in NodeVM
Keywords:
Status: NEW
Alias: CVE-2026-92958
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
high
high
Target Milestone: ---
Assignee: Product Security
QA Contact:
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2026-09-17 14:04 UTC by OSIDB Bzimport
Modified: 2026-09-17 15:47 UTC (History)
15 users (show)

Fixed In Version:
Clone Of:
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Description OSIDB Bzimport 2026-09-17 14:04:45 UTC
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.


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