Whom did Pamela Landy fax Noel Vosen’s classified documents to?

Hello. This is Pamela Landy. I have to send a classified document.

But whom was Landy talking on the phone to? Then whom was Landy faxing the classified documents to?

There's nothing in the script to indicate where she sent them, but we do know that they ended up in the possession of the FBI and a 'Senate Committee', so it's possible that Landy sent them to a friendly Senator or straight to the FBI's "Report a Crime" fax number.

ANCHOR 1 (V.O.) FBI agents arrested several senior CIA officials today in connection with the broadening scandal enveloping Washington today--

[snip]

ANCHOR 4 (V.O.) CIA Director Ezra Kramer produced explosive documents for the Senate Committee indicating “Blackbriar” was authorized at the highest levels of government.

In The Bourne Legacy, Vosen accuses her of trying to "shop" her stolen documents "to the press", so it's also possible that she sent her fax to The Guardian newspaper (who were investigating Blackbriar and Treadstone), or another news organisation with a Washington DC desk.

VOSEN: I just thank God that there were hands steady enough to make sure that the documents she tried to shop to the press were contained before they could do any more harm than they already have.

It's actually relatively unimportant where she sent the fax. The key here is that the information is so explosive that once it's out of Vosen's direct control, the whole edifice comes tumbling down.