Jaunty not even getting security updates.

I am aware of that, and partly agree, but that response falls very close to the "it's only a theoretical problem; there's no way anyone will be able to actually exploit it" argument beloved of some proprietary software companies with terrible security track records.

Bolstered by the old cryptography saw that anyone can invent a cryptosystem which they themselves are not smart enough to crack, I'm not going to claim that just because I can't think of a way to exploit this problem, it cannot be exploited. Attackers can be fiendishly devious. I'd rather err on the side of caution.