The TOCTTOU attack

Intriguing attack name isn’t it? Pronounced as TOCKTOO, this is a time-of-check/time-of-use (TOC/TOU) attack. This deals with the sequence of steps a system uses to complete a task. This type of attack takes advantage of the dependency on the timing of events that take place in a multitasking operating system. Let’s take some routine day-to-day examples to better understand this concept. Note that these examples are mentioned to help you better understand the concept. Do you love Netflix? Well, I do. When you watch a series on Netflix, you need to authenticate yourself. Let’s break this into 2 steps: Process 1: Validates your credentials to check your subscription validity. Process 2: Open up the series for you. In a TOC TOU attack, the attacker ensures that process 2 is executed before process 1. If you may wonder how can this happen, consider that operating systems and applications are, in reality, just lines and lines of instructions. An operating system must carry out instruction 1