{"id":"GHSA-27m7-ffhq-jqrm","summary":"MCP Watch has a Critical Command Injection in cloneRepo allows Remote Code Execution (RCE) via malicious URL","details":"### Summary\nThe `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.\n\n### Details\nThe vulnerability exists in the src/scanner/MCPScanner.ts file within the cloneRepo method.\n\n[https://github.com/kapilduraphe/mcp-watch/blob/0fca7228bd313ae5aa938d61311377e88ce6e682/src/scanner/McpScanner.ts#L181](https://github.com/kapilduraphe/mcp-watch/blob/0fca7228bd313ae5aa938d61311377e88ce6e682/src/scanner/McpScanner.ts#L181)\n\nThe code uses child_process.execSync to execute a git clone command:\n\nBecause execSync spawns a shell (defaulting to `/bin/sh` on Unix or` cmd.exe` on Windows), any shell metacharacters present in the url argument will be interpreted by the shell. The application does not validate that the url is a valid Git URL, nor does it sanitize input for shell metacharacters.\n\n### PoC\nInstall the package or clone the repository.\n\nRun the scanner using the CLI (or invoke scanRepository programmatically).\n\nProvide a malicious URL containing a command separator (e.g., ;, &, or |) and a system command.\npayload : `npm run scan:github \"https://github.com/kapilduraphe/mcp-watch & calc.exe\"`\n\n\u003cimg width=\"1918\" height=\"1046\" alt=\"image\" src=\"https://github.com/user-attachments/assets/021c1dfa-3f87-483c-aecb-6939bcf9c925\" /\u003e\n\n\n\n### Impact\nSeverity: **Critical**\n\n**CVSS Score**: 9.8 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)\nDescription: This vulnerability allows an attacker to execute arbitrary code on the machine running the scanner.\n\nIf run by a developer locally, it compromises their workstation.\n\nIf deployed as a hosted scanning service, it grants the attacker full control over the server (RCE), leading to potential data exfiltration, service disruption, or further lateral movement within the infrastructure.\n\n**Context Dependent Risk:**\n\nLocal CLI : If you run this tool locally on your own machine, you are \"hacking yourself.\" The risk is limited unless you copy-paste a malicious URL sent by someone else (e.g., \"Hey, check this repo scan: npm run scan \"https://git./..; rm -rf /\").\n\n**Web Service / CI Pipeline (Critical Risk)**: If this scanner is deployed as a web service (e.g., \"Paste your repo URL to scan\"), an attacker can take full control of the server immediately.","aliases":["CVE-2025-66401"],"modified":"2025-12-02T01:29:49.678864Z","published":"2025-12-02T00:38:14Z","database_specific":{"github_reviewed":true,"github_reviewed_at":"2025-12-02T00:38:14Z","nvd_published_at":"2025-12-01T23:15:53Z","cwe_ids":["CWE-78"],"severity":"CRITICAL"},"references":[{"type":"WEB","url":"https://github.com/kapilduraphe/mcp-watch/security/advisories/GHSA-27m7-ffhq-jqrm"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-66401"},{"type":"WEB","url":"https://github.com/kapilduraphe/mcp-watch/commit/e7da78c5b4b960f8b66c254059ad9ebc544a91a6"},{"type":"PACKAGE","url":"https://github.com/kapilduraphe/mcp-watch"}],"affected":[{"package":{"name":"mcp-watch","ecosystem":"npm","purl":"pkg:npm/mcp-watch"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"last_affected":"0.1.2"}]}],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2025/12/GHSA-27m7-ffhq-jqrm/GHSA-27m7-ffhq-jqrm.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"}]}