The really juicy bit about this thing is that the core developers don't want to fix it because it might prevent future vaporware uses of the bitcoin protocol to be established.
https://np.reddit.com/r/Bitcoin/comments/3nfb2y/eli5_for_double_spends_bitcoin_being_sent_twice/cvnl2wo

schemes that make malleability irrelevant are subject to dangerous signature replay attacks if not handled very carefully