---
title: "CVE-2025-66401: MCP Watch has a Critical Command Injection in cloneRepo allows Remote Code Execution (RCE) via malicious URL"
url: https://erroneo.us/security/cve/CVE-2025-66401/
description: "CVE-2025-66401 (mcp-watch (npm)): MCP Watch is a comprehensive security scanner for Model Context Protocol (MCP) servers. In 0.1.2 and earlier, the…"
type: vulnerability-record
section: "Security Digest"
date_published: 2025-12-01
date_modified: 2025-12-02
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2025-66401"
kev: false
cvss: 9.8
epss: 0.02227
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2025-66401: MCP Watch has a Critical Command Injection in cloneRepo allows Remote Code Execution (RCE) via malicious URL

**Signal:** Critical and remotely reachable. No known exploitation yet, but it is network-reachable without credentials. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- Not in CISA KEV , but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
- EPSS 2.2% , percentile 83: FIRST’s model estimates a 2.2% chance of exploitation activity in the next 30 days, higher than 83% of all scored CVEs (elevated). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes mcp-watch (npm) <= 0.1.2, no fixed version listed . Check your lockfile, including transitive dependencies.

## What it is

MCP Watch is a comprehensive security scanner for Model Context Protocol (MCP) servers. In 0.1.2 and earlier, the MCPScanner class contains a critical Command Injection vulnerability in the cloneRepo method. The application passes the user-supplied githubUrl argument directly to a system shell via execSync without sanitization. This allows an attacker to execute arbitrary commands on the host machine by appending shell metacharacters to the URL.

## Affected packages

- npm `mcp-watch` <= 0.1.2 → fixed: none listed

## Affected products (CVE record)

- kapilduraphe mcp-watch: <= 0.1.2

## Severity

- GitHub_M CVSS 3.1: 9.8 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`
- GitHub CVSS 3.1: 9.8 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation poc , automatable yes , technical impact total .
- FIRST EPSS (model of 2026-10-21): 2.23% probability of exploitation activity in the next 30 days; percentile 83.

## Sources

- [GitHub Advisory GHSA-27m7-ffhq-jqrm](https://github.com/advisories/GHSA-27m7-ffhq-jqrm)
- [CVE.org record CVE-2025-66401](https://www.cve.org/CVERecord?id=CVE-2025-66401)
- [NVD entry CVE-2025-66401](https://nvd.nist.gov/vuln/detail/CVE-2025-66401)
- [github.com](https://github.com/kapilduraphe/mcp-watch/security/advisories/GHSA-27m7-ffhq-jqrm)
- [github.com](https://github.com/kapilduraphe/mcp-watch/commit/e7da78c5b4b960f8b66c254059ad9ebc544a91a6)

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Source page: https://erroneo.us/security/cve/CVE-2025-66401/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt