Initialization vectors: Discord App - Missing values not missing

Wednesday, August 16, 2017

Discord App - Missing values not missing

* Oct 17, 2018 - Update with further insight here. *

Last post I did a quick overview of the Discord app for Android. At the time I commented that "both the messages and the usernames are missing the last letter as represented by the tools." Upon further review I figured out that
the alphabetic value of the last hex number at the end of every sentence can be decoded starting at E1h and ending at FAh.
For example the first 5 alphabetic values would be:
E1h = a
E2h = b
E3h = c
E4h = d
E5h = e
One has to only continue to map letters to hex values sequentially until the whole alphabet is represented.
By looking at the hex at the end of the sentence and comparing it to the corresponding alphabetic value one can figure out what is that last letter the tools used did not show us.
Go figure.