Someone is feeding hackers all of the bugs that were fixed in Bitcoin Core since version 0.11.2 (or whatever version Unlimited forked from). I'm guessing they slam the BU nodes with a "new" exploit monthly, to keep pace with the news cycle and have "BU HAXXED OMFG" in the headlines once per month.
Not that big of a deal. BU is not the greatest code because it doesn't have enough devs. Core is a good team doing bad work for some financial saboteurs... Choose your posion.
This doesn't look to be the case, it would appear all the crashes so far have been due to a single very buggy feature(thin/xthin blocks) that was written by BU devs, it was never present in Core.