Considerable research goes into the design of a cipher algorithm. For example, the AES cipher has gone through a world-wide evaluation, over a period of three years, before being adopted as the global standard. This thorough scrutiny has stood the test of time; there has been no cryptanalytic attack on the AES algorithm in the past two decades. However, several attacks have evolved that target the implementation of the cipher rather than its algorithmic underpinnings. These attacks, popularly know as side-channel analysis, glean secret information about the AES secret key, from channels such as the device's power consumption, electromagnetic radiation, and execution time. A side-channel attack on AES can completely decipher the secret key within a few minutes. In this seminar, I will talk about fault-injection attacks -- a class of side-channel attacks, where an attacker disturbs the AES computation to reco ver its secret key. We will discuss how the attack evolved over the years and a tool that we developed to automate the evaluation of block ciphers for fault injection attacks.