Recently I offered to the members of mypenguin99, to get my encrypted with XOR file decrypted. (I was using xor-analyze, and never mentioned the keylength, and the tool that I chose to encrypt). Bro Bahathir unsurprisingly managed to solve the problem in no time (yeah, need some time to google and decrypt). In this case we need a collision from a dictionary of widely used words, so that the real message can be guessed.
Although XOR considered a primitive cryptography, it is being used by malware writers to encrypt part of their payloads, as being written here