Comment by PoignardAzur

No, that was the 2010 "diplomatic cables" release. Basically, they disseminated an encrypted version of the data cache, and gave the decryption key to a few key people, including Guardian journalist David Leigh, with the expectation he'd report on the info without sharing sensitive intel.

David Leigh then published the decryption key in his 2011 book about Wikileaks (for some reason) and the info became publicly available. Everyone pinned the blame on Assange.

Moral of the story: journalists can and will disclose ridiculously sensitive info you give them for a bit of fame and you should be extremely careful about covering your tracks.