Summary

  • A problem with the $fallback_url in Branch.io’s deep linking system could leave users open to being redirected to phishing and malware sites by attackers using exposed API keys.
  • The anomaly occurs when a smart deep link, designed to open a specific app, is unable to do so and reverts to a programmer-provided URL as fallback.
  • This system could be abused when an attacker exposes an API key and uses a wildcard $fallback_url, allowing for malicious redirections and compromising user data through false prompts for login details.
  • The article warns developers to keep API keys secret to avoid exposing users to such risks and also to regularly monitor $fallback_url to ensure security.

By Mrunal chawda

Original Article