CVE-2026-92952
vm2 versions 3.11.4 through 3.11.6 incompletely filter Node.js registered internal symbols across the sandbox boundary. The extraction filters in lib/setup-sandbox.js and the cross-realm symbol checks and write traps in lib/bridge.js use a fixed list of known dangerous registered symbols that omits nodejs.stream.disturbed and nodejs.stream.errored, which are exposed on host WebStream prototypes on newer Node.js releases (validated on Node.js v25.8.0). When the embedder exposes a host WebStream object and the host stream/web module to the sandbox, sandbox code can obtain the real host symbols via Object.getOwnPropertySymbols(streamWeb.ReadableStream.prototype) and use them as write keys on host stream objects, corrupting host-visible stream state — for example making stream.Readable.isDisturbed() return false for an already-consumed stream. This can bypass host logic that relies on Node's public stream-state helpers to enforce one-shot body consumption, reject errored streams, or decide whether a stream is safe to hand to another component. It is not a host code-execution primitive in the reported proof of vulnerability. This is an incomplete fix for the earlier nodejs.* symbol filtering issue. Fixed in vm2 3.11.7.
What this means for your business
- An attacker can use it remotely, over a network, without a login, and without anyone at your company clicking anything.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
Not sure if your company is exposed?
Fastnexa’s certified penetration testers can check whether attackers could use this flaw, or others like it, against your websites, apps and network. The full test is free for our first 10 founding clients until 31 December 2026.
Scoring
- CVSS
- 6.8 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:H/A:N- CVSS v4
- 8.9
- Weakness
- CWE-669
- Assigned by
- disclosure@vulncheck.com
Dates
- Published
- 2026-09-17
- Last modified
- 2026-09-17
- Sources
- NVD