Mobile App Credential Extraction

What Is This Vulnerability

Mobile App Credential Extraction is a compound vulnerability where multiple secrets, API keys, tokens, and credentials can be extracted from a mobile application through reverse engineering. Rather than a single hardcoded key, this finding indicates a systemic pattern of embedding sensitive credentials throughout the app — in source code, configuration files, shared preferences, and bundled resources.

This vulnerability is identified when three or more distinct credentials are found during analysis, suggesting a fundamental architectural issue where the mobile app is treated as a trusted environment.

Why It's Dangerous

Multiple extracted credentials compound the risk exponentially:

• Broad attack surface — each credential opens a different attack vector (database access, payment processing, email sending, cloud storage).
• Lateral movement — credentials for one service often contain information (project IDs, account identifiers) that helps compromise others.
• Difficult remediation — rotating a single key is straightforward; rotating many keys across multiple services requires coordinated effort and can cause downtime.
• Supply chain risk — third-party SDK keys may grant access to shared resources or partner systems.
• Persistent access — attackers can use different credentials as fallbacks if one is rotated, maintaining access until all are revoked.

A typical extraction might yield a Supabase anon key, a Firebase config, a Stripe publishable key, an analytics API key, and a push notification server key — each enabling different types of abuse.

How to Detect

Perform comprehensive static analysis on the mobile binary:

# Full credential scan for Android APK
jadx -d output/ app.apk

# Run a comprehensive secret scan
grep -rn "eyJhbGciOi" output/           # JWT tokens
grep -rn "AIza[0-9A-Za-z_-]\{35\}" output/  # Google/Firebase
grep -rn "sk_live\|sk_test" output/      # Stripe secret keys
grep -rn "pk_live\|pk_test" output/      # Stripe publishable keys
grep -rn "AKIA[0-9A-Z]\{16\}" output/   # AWS Access Keys
grep -rn "sk-[a-zA-Z0-9]\{20,\}" output/ # OpenAI keys
grep -rn "xoxb-\|xoxp-" output/          # Slack tokens
grep -rn "SG\.[a-zA-Z0-9]\{22\}" output/ # SendGrid keys
grep -rn "key-[a-zA-Z0-9]\{32\}" output/ # Mailgun keys

# Check resource and config files
find output/ -name "*.xml" -o -name "*.json" -o -name "*.plist" |   xargs grep -l "key\|secret\|token\|password"

AuditYour.app runs over 100 regex patterns against decompiled mobile apps and correlates findings to map out the full credential exposure surface.

How to Fix

Adopt a zero-trust architecture for mobile clients:

// Backend proxy pattern — mobile app never holds sensitive keys
// Mobile app authenticates user, backend handles all privileged operations

// Server-side (Edge Function / API route)
app.post('/api/send-email', authenticate, async (req, res) => {
  // SendGrid key stays server-side
  const sg = new SendGrid(process.env.SENDGRID_API_KEY);
  await sg.send({ to: req.body.to, subject: req.body.subject });
  res.json({ success: true });
});

app.post('/api/create-payment', authenticate, async (req, res) => {
  // Stripe secret key stays server-side
  const stripe = new Stripe(process.env.STRIPE_SECRET_KEY);
  const intent = await stripe.paymentIntents.create({
    amount: req.body.amount,
    currency: 'usd',
    customer: req.user.stripeCustomerId,
  });
  res.json({ clientSecret: intent.client_secret });
});

Establish a credential management checklist:

1. Audit every key in the mobile codebase and classify as public (safe to embed) or secret (must be server-side).
2. Move all secret keys to environment variables on your backend.
3. Implement API proxy endpoints for every third-party service.
4. Use platform-specific secure storage (Android Keystore, iOS Keychain) for any runtime tokens.
5. Add automated secret scanning to your CI/CD pipeline to catch regressions.