Application data at rest: With the introduction of mobile applications, the concept of storing data at the client side has been drastically adopted. Many mobile applications store sensitive data on the device without any encryption. This is one of the major problems of mobile applications. This data can be sensitive, confidential, and private. Data that rests on the device can be exploited in many different ways. An attacker who has got physical access to the device can gain access to this data almost without doing anything. A malicious application may gain access to this data if the device is rooted/jailbroken. It is important to make sure that apps do not store sensitive data such as usernames, passwords, authentication tokens, credit card numbers, and so on, on the device. If it cannot be avoided, it is required to encrypt it and keep it away from an attacker's control. We will explore more details about insecure data storage vulnerabilities in Chapter 5, Data...