Security Analysis

Is Firebase Safe?

Last updated: January 12, 2026

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

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.

Understanding Firebase Security

When evaluating whether Firebase is safe for your project, it's important to understand the distinction between platform security and application security. Firebase as a platform implements industry-standard security practices for its infrastructure, including encryption, access controls, and regular security audits.

However, the security of applications built with Firebase depends significantly on how developers use the platform. AI-generated code and rapid development workflows can introduce vulnerabilities that exist independently of the platform's underlying security. Research from Stanford University found that AI coding assistants produce vulnerable code approximately 40% of the time when working on security-sensitive tasks.

The most common security issues in Firebase applications stem from misconfigurations, exposed credentials, and missing security controls—problems that developers must address regardless of which platform they use. Understanding these patterns helps you make informed decisions about using Firebase for your specific use case.

Platform Security

Platform security refers to the security measures Firebase implements at the infrastructure level: how they protect their servers, encrypt data in transit and at rest, manage access to their systems, and respond to security incidents. These are controls the platform provider manages on your behalf.

Application Security

Application security is your responsibility as a developer. This includes properly configuring authentication, implementing authorization controls, protecting sensitive data, securing API endpoints, and avoiding common vulnerabilities like exposed credentials or SQL injection. These risks exist regardless of which platform you use.

Common Security Mistakes in Firebase Apps

Based on security scans of thousands of Firebase applications, these are the most frequently encountered vulnerabilities. Understanding these patterns helps you proactively secure your applications.

Exposed API Keys & Secrets

AI coding tools frequently embed API keys, database credentials, and other secrets directly in JavaScript bundles. These credentials become visible to anyone who inspects your application's source code in their browser.

Prevention: Use environment variables and server-side API routes to keep credentials secure.

Missing Database Security

Applications using Supabase or Firebase often launch without proper Row Level Security (RLS) policies or Security Rules. This allows unauthorized users to read, modify, or delete data they shouldn't have access to.

Prevention: Always enable and test RLS policies before deploying to production.

Insufficient Input Validation

AI-generated code often assumes valid input without implementing proper validation. This opens applications to injection attacks, XSS vulnerabilities, and data corruption.

Prevention: Validate all user input on both client and server side.

Missing Security Headers

HTTP security headers like Content-Security-Policy, X-Frame-Options, and Strict-Transport-Security are frequently missing from AI-generated applications, leaving them vulnerable to various attacks.

Prevention: Configure security headers in your hosting platform or application middleware.

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 WillisonSecurity 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 CommunityCollective 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

Don't guess - scan your app and know for certain. VAS checks for all the common security issues in Firebase applications.