vm2: Incomplete nodejs.* symbol filtering lets sandbox override host WebStream state checks

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

6.8 · CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:H/A:N

EPSS

• CVE-2026-92952: 0.46% estimated exploitation activity in the next 30 days; percentile 39.99 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary vm2 current head (v3.11.5, commit 7a1f5100b96f48d34e0fe104ab37c0acc5944f92) still exposes registered Node.js internal symbols from host WebStream prototypes to sandbox code. The prior nodejs. symbol hardening blocks Symbol.for('nodejs.<name') at the source, but the extraction filters and bridge write traps still enumerate a fixed set of known registered symbols. On Node.js v25.8.0, stream/web exposes two additional registered symbols: - nodejs.stream.disturbed - nodejs.stream.errored Sandbox code can extract those real host symbols with Object.getOwnPropertySymbols(streamWeb.ReadableStream.prototype) and then use them as write keys on host objects. On a real host ReadableStream, an attacker can make stream.Readable.isDisturbed(stream) return false after the stream has already been read. Technical Details lib/setup-sandbox.js correctly blocks future nodejs. keys at the Symbol.for() source: However, the extraction filters are still driven by a fixed realDangerousSymbols list.…

Published by the source

1 Oct 2026, 15:42 UTC

Last modified by the source

1 Oct 2026, 16:00 UTC

Source last checked

26 Oct 2026, 13:06 UTC

1. Revision 3 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-jf8q-945g-9q4c

2. Revision 2 · amended · 24 Oct 2026

   Amended from osv record GHSA-jf8q-945g-9q4c

3. Revision 1 · created · 23 Oct 2026

   Published from ghsa record GHSA-jf8q-945g-9q4c

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# Patch Next advisory brief: CVE-2026-92952

Advisory: vm2: Incomplete nodejs.* symbol filtering lets sandbox override host WebStream state checks
IDs: CVE-2026-92952, GHSA-jf8q-945g-9q4c
Record: https://patchnext.com/advisories/cve-2026-92952 (revision 3, source checked 26 Oct 2026, 13:06 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 6.8)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: vm2 3.11.7. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm vm2: affected >= 3.11.4, <= 3.11.6; fixed in 3.11.7

## Suggested inspection (read-only)
- `npm ls vm2 --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on vm2.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-jf8q-945g-9q4c (GitHub-reviewed advisory GHSA-jf8q-945g-9q4c lists affected ranges: npm vm2 >=3.11.4 <=3.11.6)
- Verified: https://osv.dev/vulnerability/GHSA-jf8q-945g-9q4c (OSV record GHSA-jf8q-945g-9q4c lists affected ranges: npm vm2 >=3.11.4 <3.11.7 (fixed))

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