The Britney & Heidi Duet - Is This Even Legal?

Ryan Seacrest's people told X17online that they received this track of Heidi Montag dueting with Britney Spears from a producer that wanted to remain anonymous.
The duet, in which Heidi's practically unitelligible vocals were apparently mixed with Britney's in an old demo, almost makes me ill, but is it illegal as well?
Although it's possible that the producer owns the track, who owns the right to Britney's vocals?
We've put in a call to Jive, are waiting to hear their take on the track...
Stay tuned!
Obviously this is a publicity stunt (that's working!), but Spencer & Heidi - you've gone TOO FAR!
> X17 XCLUSIVE - BRITNEY'S TOUR BODY IS BANGIN! - Apr 19, 2009
> What's It Like To Go Backstage At Brit's Show? - Apr 18, 2009
> Stalker Enters Britney's Home Before LA Concert!!! - Apr 16, 2009
> It's Britney, B*tch!!! - Apr 16, 2009











