# CVE-2026-92952: vm2 3.11.4 through 3.11.6 Sandbox Symbol Filtering Bypass

> Attackers can bypass sandbox stream state checks by exploiting unfiltered internal symbols, potentially corrupting host stream logic in vm2.

- **Severity:** High 8.9 (`CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:H/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 17 Sep 2026
- **Updated:** 17 Sep 2026
- **Also known as:** CLEANSTART-2026-FF64850, ECHO-e013-9d17-e16a, GHSA-jf8q-945g-9q4c, MINI-whrw-7pmq-2wgp

## What is CVE-2026-92952?

CVE-2026-92952 is a high-severity vulnerability in patriksimek vm2, published on 17 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

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.

Weakness: CWE-669 (Incorrect Resource Transfer Between Spheres)

## Which versions are affected by CVE-2026-92952?

2 open source packages ship an affected version, including vm2.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `vm2` | npm | From 3.11.4 | 3.11.7 |
| `vm2` | npm | From 3.11.4 | 3.11.7 |

## How do I fix CVE-2026-92952?

Upgrade vm2 to 3.11.7 or later.

## Is CVE-2026-92952 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-92952 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-92952 and fix it if it is affected.

What it is: CVE-2026-92952 is a high-severity vulnerability in patriksimek vm2, published on 17 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-92952 exists.

Affected packages and fixed versions:
- vm2 (npm): affected from 3.11.4; fixed in 3.11.7
- vm2 (npm): affected from 3.11.4; fixed in 3.11.7

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-92952/ (Markdown: https://insights.sbomify.com/CVE-2026-92952/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-92952
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-92952
- OSV: https://osv.dev/vulnerability/CVE-2026-92952

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-92952/
Summaries are generated and may contain mistakes; the official description above is the record.