Nope. Trump is behind it. National enquirer does his bidding.
Meanwhile: http://www.thedailybeast.com/articles/2016/03/25/ted-cruz-affair-rumors-peddled-by-marco-rubio-s-allies.html
The truth behind the rumor-mongering, however, is a little more complex. A half-dozen GOP operatives and media figures tell The Daily Beast that Cruz’s opponents have been pushing charges of adultery for at least six months now—and that allies of former GOP presidential hopeful Marco Rubio were involved in spreading the smears.