I actually find this kind of amusing, since it was a benign attack. I didn't try to log into Obama's blog site today, but apparently a trickster managed to post some code that was redirecting visitors over to HRC's site.  As noted in the article I linked, the HRC site has an identical vulnerability that was exploited here, so before folks start pointing fingers at the Clinton campaign, consider how silly it would be to intentionally exploit a flaw that you leave open for exploitation on your own site.  Glad to see nothing truly nefarious ensued.