Firebase Cloud Messaging Security¶

Firebase Cloud Messaging (FCM) enables sending push notifications to mobile and web applications, but requires careful security configuration to prevent abuse.

Overview¶

FCM provides a reliable and battery-efficient connection between your server and devices to deliver and receive messages and notifications. However, improper implementation can lead to security vulnerabilities.

Common Security Issues¶

Message Security¶

• Insecure Firebase Cloud Messaging - Server key exposure and insecure configuration

Best Practices¶

Authentication and Authorization¶

1. Never expose server keys in client-side code
2. Use FCM HTTP v1 API with OAuth 2.0 authentication
3. Implement server-side validation for all messaging operations
4. Use topic-based messaging with proper access controls

Content Security¶

1. Avoid sensitive data in notification payloads
2. Validate notification content to prevent injection attacks
3. Use HTTPS for all FCM communications
4. Implement rate limiting to prevent abuse

Monitoring¶

1. Log all FCM operations for security auditing
2. Monitor for suspicious patterns in message sending
3. Track notification delivery rates and failures
4. Regular security reviews of FCM implementation