Cut the budget and fire one in ten CIA employees, selected at random.
If the leaks don't stop, move on tho the NSA, DIA, etc. one after the other until they get back around to the CIA. I have a feeling that by the time Trump works his way through all seventeen agencies the leaks will have stopped.
Too bad we can't perform the practice in the traditional Roman way. It would be much better for national security.
Start those who were hired by Obama.
Just offer a $100,000 reward for info leading to those who have leaked classified materials to the media. Subject these suspects to intense rendition techniques.