---
id: CVE-2026-49856
title: >-
  @jshookmcp/jshook is an MCP server that gives AI agents tools for JavaScript
  analysis and security research
summary: >-
  @jshookmcp/jshook is an MCP server that gives AI agents tools for JavaScript
  analysis and security research. In version 0.3.1, he network domain has a
  central SSRF authorization policy that blocks private, loopback, link-local,
  and reser…
severity: medium
cvss: 4.3
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N'
cwe:
  - CWE-918
vendor: jshookmcp
product: '@jshookmcp/jshook'
affected:
  - '@jshookmcp/jshook = 0.3.1'
patched:
  - '@jshookmcp/jshook 0.3.2'
published: '2026-08-13'
updated: '2026-09-18'
sourceUpdated: '2026-09-18T20:09:01.757'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-49856'
references:
  - url: >-
      https://github.com/vmoranv/jshookmcp/commit/02111311f7bd0f86a7d7ef8538986594b3a18afa
    label: security-advisories@github.com
  - url: >-
      https://github.com/vmoranv/jshookmcp/security/advisories/GHSA-c5r6-m4mr-8q5j
    label: security-advisories@github.com
  - url: >-
      https://github.com/vmoranv/jshookmcp/security/advisories/GHSA-c5r6-m4mr-8q5j
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
  - url: 'https://github.com/advisories/GHSA-c5r6-m4mr-8q5j'
tags:
  - nvd
  - ghsa
  - npm
epss: 0.00281
epssPercentile: 0.18265
ecosystem: npm
ingestedAt: '2026-07-01T19:15:59.926Z'
---

## Overview

@jshookmcp/jshook is an MCP server that gives AI agents tools for JavaScript analysis and security research. In version 0.3.1, he network domain has a central SSRF authorization policy that blocks private, loopback, link-local, and reserved targets unless an explicit authorization object allows private network access. The policy is enforced by raw HTTP/TCP/TLS RTT tools, but the ICMP probe and traceroute tools resolve the target and invoke the native ICMP/traceroute sink directly. An MCP client with access to an active network domain can therefore ask the jshookmcp server to probe internal addresses even when local SSRF access is disabled for the other raw network tools. This exposes an internal reachability and route mapping primitive from the server network position. Version 0.3.2 fixes the issue.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Package advisory (CVE-2026-49856)

Affected packages:

- `@jshookmcp/jshook = 0.3.1`

Patched in:

- `@jshookmcp/jshook 0.3.2`

Source: https://github.com/advisories/GHSA-c5r6-m4mr-8q5j