Security Analysis

Is Firebase Safe?

Last updated: January 12, 2026

An honest security analysis of Firebase for developers considering it for their projects.

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Quick Answer

Safe when Security Rules replace test mode - Google infrastructure

Firebase is secure when Security Rules are properly configured. TEST MODE IS THE #1 DANGER - it grants public read/write access to your entire database. Firebase API keys are intentionally public (unlike traditional secrets). Security comes from Security Rules, not key hiding.

Security Assessment

Security Strengths

  • Google Cloud infrastructure - same security as Gmail, YouTube, Google Cloud
  • Security Rules run server-side on Google's servers - cannot be bypassed by clients
  • Firebase Emulator allows testing rules locally before deploying
  • App Check prevents abuse from unauthorized apps/bots
  • Admin SDK + Cloud Functions keep sensitive operations server-side

Security Concerns

  • TEST MODE rules (allow read, write: if true) expose your ENTIRE database publicly
  • Firebase console often defaults to test mode during setup
  • Security Rules syntax is Firebase-specific, not transferable (unlike SQL-based Supabase RLS)
  • No row-level filtering by default - must implement user-based access in rules
  • Firestore rules can timeout on complex queries, potentially allowing unintended access

Security Checklist for Firebase

  • 1
    Replace test mode: Delete 'allow read, write: if true;' from firebase.json Security Rules
  • 2
    Check auth in rules: match /users/{userId} { allow read, write: if request.auth.uid == userId; }
  • 3
    Test with Emulator: firebase emulators:start then try unauthorized reads in console
  • 4
    Enable App Check in Firebase Console to prevent API abuse from unauthorized sources
  • 5
    For sensitive operations: use Cloud Functions with Admin SDK (bypasses rules safely server-side)
  • 6
    Review Firestore Rules tab in Firebase Console for warnings about permissive rules

The Verdict

Firebase is backed by Google's enterprise infrastructure - the platform is not the vulnerability. TEST MODE is the #1 cause of Firebase data breaches. Unlike Supabase (SQL-based RLS), Firebase uses proprietary Security Rules syntax. The API key is meant to be public. Check your Security Rules and delete test mode before production.

Security Research & Industry Data

Understanding Firebase security in the context of broader industry trends and research.

10.3%

of Lovable applications (170 out of 1,645) had exposed user data in the CVE-2025-48757 incident

Source: CVE-2025-48757 security advisory

91%

of data breaches involve databases with misconfigured access controls

Source: Verizon Data Breach Investigations Report

4.45 million USD

average cost of a data breach in 2023

Source: IBM Cost of a Data Breach Report 2023

What Security Experts Say

“Vibe coding your way to a production codebase is clearly risky. Most of the work we do as software engineers involves evolving existing systems, where the quality and understandability of the underlying code is crucial.”

Simon Willison — Security Researcher, Django Co-creator

“The problem with AI-generated code isn't that it doesn't work - it's that it works just well enough to ship, but contains subtle security flaws that are hard to spot.”

Security Research Community — Collective wisdom from security researchers

Frequently Asked Questions

Is Firebase safe for production apps?

Yes, Firebase runs on Google Cloud infrastructure and is SOC 2 compliant. However, test mode Security Rules (allow read, write: if true) expose your entire database. The platform is secure; your Security Rules configuration determines app security.

Why is my Firebase API key public in my code?

Firebase API keys are designed to be public - they identify your project to Google services but don't grant data access. This is different from traditional API keys. Security comes from Security Rules, not from hiding the Firebase config. The apiKey is not a secret.

What is Firebase test mode and why is it dangerous?

Test mode sets Security Rules to 'allow read, write: if true' which grants ANYONE public read/write access to your entire database. Firebase console often defaults to test mode during setup. You MUST replace these rules before production. Check firebase.json and Firestore Rules tab.

How are Firebase Security Rules different from Supabase RLS?

Firebase Security Rules use a proprietary JSON-like syntax specific to Firebase. Supabase uses standard PostgreSQL Row Level Security (SQL). Firebase rules are simpler but less powerful for complex queries. Both achieve access control but RLS skills transfer across PostgreSQL databases.

How do I test if my Firebase Security Rules are secure?

Use Firebase Emulator: 'firebase emulators:start', then try reading data as an unauthenticated user. Also check the Firestore Rules tab in Firebase Console - it shows warnings about permissive rules. Never rely on client-side testing; rules run server-side.

Verify Your Firebase App Security

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Related Security Guides

Firebase Security ScannerFirebase Security GuideVibe Coding SecurityRLS Misconfiguration GuideAPI Key ExposureSupabase SecurityFirebase Security