In this chapter, we provide information on how to check your code, your dependencies, and your environment for potential threats. Keep in mind, though, that following every step outlined within this chapter won't necessarily protect you against all possible problems. Our aim is to show you some possible dangers and the ways to deal with them. Given this, you should always be conscious of the security of your system and make audits a routine event.
Before the internet became ubiquitous, software authors weren't too concerned about the security of their designs. After all, if the user presented malformed data, the user could crash their own computer at most. In order to use software vulnerabilities to access protected data, the attacker had to obtain physical access to the machines holding the data.
Even in software that was designed to be used within networks, security was often an afterthought. Take the Hypertext Transfer Protocol (HTTP) as an...