Debugger port 5858 listens on any interface by default: When the debugger is enabled with node --debug or node debug, it listens to port 5858 on all interfaces by default. This may allow remote…

Exploitation

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

CVSS

not scored

EPSS

• CVE-2018-12120: 4.28% estimated exploitation activity in the next 30 days; percentile 91.11 (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.

Debugger port 5858 listens on any interface by default: When the debugger is enabled with `node --debug` or `node debug`, it listens to port 5858 on all interfaces by default. This may allow remote computers to attach to the debug port and evaluate arbitrary JavaScript. The default interface is now localhost. It has always been possible to start the debugger on a specific interface, such as `node --debug=localhost`. The debugger was removed in Node.js 8 and replaced with the inspector, so no versions from 8 and later are vulnerable.

Published by the source

27 Nov 2018, 00:00 UTC

Last modified by the source

27 Nov 2018, 00:00 UTC

Source last checked

26 Oct 2026, 16:35 UTC

1. Revision 2 · published · 26 Oct 2026

   Published from vendor_advisory record nodejs-security-wg:core:56

2. Revision 1 · created · 26 Oct 2026

   Created from vendor_advisory record nodejs-security-wg:core:56

Preview the exact text before you copy it. Commands are read-only suggestions; review them before running anything.

# Patch Next advisory brief: CVE-2018-12120

Advisory: Debugger port 5858 listens on any interface by default: When the debugger is enabled with `node --debug` or `node debug`, it listens to port 5858 on all interfaces by default. This may allow remote…
IDs: CVE-2018-12120
Record: https://patchnext.com/advisories/cve-2018-12120 (revision 2, source checked 26 Oct 2026, 16:35 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Unrated
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: node 8.14.0, 6.15.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- runtime node: affected >= 6.0.0, < 6.15.0; >= 8.0.0, < 8.14.0; fixed in 6.15.0, 8.14.0

## Suggested inspection (read-only)
- runtime node: check the installed version with your package manager.

## 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 node.
- 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://nodejs.org/dist/index.json (The nodejs.org release index dates the first patched release for CVE-2018-12120 to 2018-11-27.)
- Verified: https://raw.githubusercontent.com/nodejs/security-wg/main/vuln/core/56.json (Node.js security working group core entry 56 lists CVE-2018-12120 affecting node >=6.0.0 =8.0.0 <8.14.0)

Commands are suggestions: review each one before running it.