It was sitting on the shelf.

"Morales explained that Access Hollywood discovered the audio recording when they were sifting through old interviews conducted with the real estate mogul after reports that he made demeaning comments about women during his time as host of The Apprentice, which, like Access, is an NBC show."

http://www.usmagazine.com/entertainment/news/nancy-odell-is-the-married-woman-donald-trump-bragged-about-hitting-on-w443999

Supposedly Access Hollywood was planning to cover the story, but not until later. Someone there at NBC apparently went rogue to make sure it came out and sooner rather than later, before the next debate by leaking it to Post

If it was on servers it could have been anybody with access to the server. Or it really could have been a hack from outside. Until it is looked in to further it's just a "belief"

"But sources at NBC believe someone inside NBC downloaded the footage from one of the network's video servers. The tape was accessible internally since the "Access" story was already in the works.


Fair use link
http://money.cnn.com/2016/10/07/media/access-hollywood-donald-trump-tape/index.html

They've known about this, and God knows what else, for months. They're strategically leaking stuff in bits and pieces as things get closer. Brilliant strategy. All's fair in love, war and politics!

Access Hollywood was prepping this for release. But it got released early by someone.