Usually when the United States federal government releases anything it defaults into the public domain.
Also, elements of the intelligence community have made statements that suggest that applicants to some government positions could be refused if they tweet or say anything about Wikileaks. [1]
1. http://dailycaller.com/2010/12/09/schools-warn-students-not-...
http://leaksource.wordpress.com/2013/04/08/wikileaks-plusd-p...
So it is legal
If the materials were still classified-but-leaked then I won't go near it until it is declassified. But I can't tell from this side of the window what's going on.