Alpha Vantage API

• Outcome: Review
• Latest audit: Sep 11, 2026 · 3:47 AM UTC
• Version: 1.0.0

Overview

This Alpha Vantage skill appears purpose-aligned, but it handles the user's API key in ways that can expose it locally or in logs.

Review this skill before installing if you plan to use a personal Alpha Vantage key. Prefer the demo key or a low-privilege/rotatable key, avoid running the documented apikey command where shell history or logs are captured, and rotate any key that was already printed or stored by the tool.

A.I.G

Vulnerability Patterns

• Insecure Skill Coding Practices: Finds exploitable flaws such as hardcoded secrets or command injection
• Skill Instruction Hijacking: Alters the agent's session goals or safety constraints when the skill loads
• Agent Memory Poisoning: Writes attacker-controlled rules into memory that affect later sessions
• Remote Payload Retrieval and Execution: Fetches external code whose behavior can change after review
• Embedded Malicious Code: Ships malicious scripts inside the skill and executes them locally

Findings (1)

T09 · Insecure Skill Coding Practices

Warning

• Location: alpha.js:29

Finding

Insecure API Key Exposure Through Command-Line Arguments, Output, Plaintext Storage, and Request URLs

Content

View full analysis

Vulnerability Details

File Location: SKILL.md:25-29; alpha.js:29-34; alpha.js:68; alpha.js:104; alpha.js:144; alpha.js:184; alpha.js:224; alpha.js:251; alpha.js:317-326
Vulnerability Type: Sensitive credential exposure and insecure secret storage
Risk Level: Medium

Vulnerable Code

SKILL.md:25-29 documents passing the API key as a command-line argument:

bash

# Use your own API key
node alpha.js apikey YOUR_API_KEY

alpha.js:29-34 stores the key in a plaintext JSON file without explicitly restrictive permissions:

javascript

// Save configuration
function saveConfig() {
  fs.writeFileSync(CONFIG_FILE, JSON.stringify(config, null, 2));
}

alpha.js:317-326 reads the secret directly from the command line, persists it, and prints the complete value:

javascript

case 'apikey':
  if (!args[1]) {
    console.error('Please provide an API key');
    process.exit(1);
  }
  config.apiKey = args[1];
  saveConfig();
  console.log(`API key has been set to: ${args[1]}`);
  process.exit(0);

The original source contains equivalent user-facing messages in Chinese. The security-relevant behavior is the direct use and disclosure of args[1].

The key is also embedded in request URLs at alpha.js:68, 104, 144, 184, 224, and 251:

javascript

const url = `https://www.alphavantage.co/query?function=GLOBAL_QUOTE&symbol=${symbol}&apikey=${config.apiKey}`;

javascript

const url = `https://www.alphavantage.co/query?function=TIME_SERIES_DAILY&symbol=${symbol}&outputsize=${outputSize}&apikey=${config.apiKey}`;

javascript

const url = `https://www.alphavantage.co/query?function=TIME_SERIES_WEEKLY&symbol=${symbol}&apikey=${config.apiKey}`;

javascript

const url = `https://www.alphavantage.co/query?function=TIME_SERIES_MONTHLY&symbol=${symbol}&apikey=${config.apiKey}`;

j

...[truncated 2805 chars]

Remediation

View remediation

Remediation Suggestions

1. Do not accept secrets as ordinary command-line arguments.

   • Prefer the existing ALPHA_KEY environment-variable mechanism for noninteractive execution.
   • For interactive configuration, read the key from a masked prompt or standard input without echoing it.
   • Update SKILL.md so it no longer recommends node alpha.js apikey YOUR_API_KEY.

2. Never print the complete credential.

   • Replace the current confirmation with a generic message such as API key configured successfully.
   • If identification is necessary, display only a small masked suffix, such as ****1234.

3. Use secure credential storage.

   • Prefer an operating-system credential manager or secret-management service.
   • If local file storage remains necessary, create the file with owner-only permissions and verify permissions after creation:

   javascript

   fs.writeFileSync(
     CONFIG_FILE,
     JSON.stringify(config, null, 2),
     { encoding: 'utf8', mode: 0o600 }
   );
   fs.chmodSync(CONFIG_FILE, 0o600);
   

   • Ensure config.json is excluded from version control, backups, support bundles, and artifact packaging where appropriate.

4. Minimize URL-based credential exposure.

   • Avoid logging complete request URLs.
   • Redact apikey values in diagnostics, telemetry, proxy logs, and exception reports.
   • If the upstream API supports a credential header, use that mechanism instead of a query parameter. If Alpha Vantage requires a query parameter, constrain logging and instrumentation accordingly.

5. Rotate exposed keys.

   • Any key previously supplied through the documented CLI command, printed to logs, or stored with permissive access should be treated as potentially disclosed and replaced.

SkillSpector

Vulnerability Patterns

• Prompt Injection: Instruction Override, Hidden Instructions, Exfiltration Commands
• Data Exfiltration: External Transmission, Env Variable Harvesting, File System Enumeration
• Privilege Escalation: Excessive Permissions, Sudo/Root Execution, Credential Access
• Supply Chain: Unpinned Dependencies, External Script Fetching, Obfuscated Code
• Excessive Agency: Unrestricted Tool Access, Autonomous Decision Making, Scope Creep

Findings (1)

Natural-Language Policy Violations

Medium

• Category: Not specified by scanner
• Confidence: 95% confidence

Finding

This JavaScript file presents its description, help text, prompts, and errors entirely in Chinese, which constitutes a locale/language constraint embedded in natural-language strings. The file does not offer any user opt-in, fallback language, or documented justification for restricting output to Chinese.

Content

No source excerpt is available for this finding.

Static analysis

No suspicious patterns detected.