@Mockoon/commons-server: Unauthenticated admin API + wildcard CORS allows mock-state hijack and secret theft

Exploitation

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

CVSS

8.8 · CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

EPSS

• CVE-2026-59148: 0.26% estimated exploitation activity in the next 30 days; percentile 18.12 (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 Mockoon's admin API (commons-server/src/libs/server/admin-api.ts) is mounted on the same Express listener as the user-defined mock routes, enabled by default in every shipped runtime (commons-server, CLI, serverless), serves Access-Control-Allow-Origin: on every endpoint with all HTTP methods allowed including PUT/POST/PATCH/DELETE/PURGE and Content-Type in Access-Control-Allow-Headers, and has zero authentication of any kind (no token, no shared secret, no MOCKOONADMINTOKEN env var — searched the repo, returns zero hits). Any unauthenticated caller who can reach the mock server's port (default 0.0.0.0:3000) can: - Read every MOCKOON env var used by the operator as secret material in templates (getEnvVar helper). - Write arbitrary process env vars (no prefix check on the WRITE path) — poison operator's MOCKOONAPIKEY, MOCKOONJWTSECRET, …, or write process-level vars like AWSSECRETACCESSKEY that the surrounding runtime consumes. - Rewrite every mock route's body / status /…

Published by the source

11 Sep 2026, 22:04 UTC

Last modified by the source

11 Sep 2026, 22:15 UTC

Source last checked

26 Oct 2026, 13:02 UTC

1. Revision 3 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-rqx4-3f6q-3x2v

2. Revision 2 · amended · 24 Oct 2026

   Amended from osv record GHSA-rqx4-3f6q-3x2v

3. Revision 1 · created · 23 Oct 2026

   Published from ghsa record GHSA-rqx4-3f6q-3x2v

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# Patch Next advisory brief: CVE-2026-59148

Advisory: @Mockoon/commons-server: Unauthenticated admin API + wildcard CORS allows mock-state hijack and secret theft
IDs: CVE-2026-59148, GHSA-rqx4-3f6q-3x2v
Record: https://patchnext.com/advisories/cve-2026-59148 (revision 3, source checked 26 Oct 2026, 13:02 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 8.8)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: @mockoon/cli 9.7.0; @mockoon/commons-server 9.7.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm @mockoon/cli: affected < 9.7.0; fixed in 9.7.0
- npm @mockoon/commons-server: affected < 9.7.0; fixed in 9.7.0

## Suggested inspection (read-only)
- `npm ls @mockoon/cli --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.
- `npm ls @mockoon/commons-server --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 @mockoon/cli, @mockoon/commons-server.
- 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-rqx4-3f6q-3x2v (GitHub-reviewed advisory GHSA-rqx4-3f6q-3x2v lists affected ranges: npm @mockoon/commons-server >=0 =0 <9.7.0)
- Verified: https://osv.dev/vulnerability/GHSA-rqx4-3f6q-3x2v (OSV record GHSA-rqx4-3f6q-3x2v lists affected ranges: npm @mockoon/commons-server >=0 =0 <9.7.0 (fixed))

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