I was under the impression that they were planting files on the user's computer to incriminate them. I don't really understand where this code is getting it's payload from though.
[1] https://github.com/hackedteam/rcs-common/blob/38290d4eab2b2c...
[2] https://github.com/hackedteam/rcs-common/blob/38290d4eab2b2c...