The basics – hashing

One of the most useful techniques an analyst has at their disposal is hashing. A hashing algorithm is a one-way function that generates a unique checksum for every file, much like a fingerprint of the file.

That is to say, every unique file passed through the algorithm will have a unique hash, even if only a single bit differs between two files. For instance, in the previous chapter, we utilized SHA256 hashing to verify whether a file that was downloaded from VirtualBox was legitimate.

Hashing algorithms

SHA256 is not the only hashing algorithm you're likely to come across as an analyst, though it is currently the most reliable in terms of balance of lack of collision and computational demand. The following table outlines hashing algorithms and their corresponding bits:

Analysis Tip

In terms of hashing, collision is an occurrence where two different files have identical hashes. When a collision occurs, a hashing...