Mobile security researchers have discovered unprotected Firebase databases of thousands of iOS and Android mobile applications exposed over 100 million data records. Google’s Firebase service does not secure user data by default, requiring developers to explicitly implement user authentication on all database rows and tables to protect their databases from unauthorized access. Researchers scanned over 2.7 million apps and found that more than 3,000 apps were leaking a whole 2,300 databases with more than 100 million records, making it a giant breach of over 113 gigabytes of data.
Source: https://thehackernews.com/2018/06/mobile-security-firebase-hosting.html