UPDATE -- 7:20 p.m. PT -- A representative of Kevin Yorn denies the accusation telling Radar, "This is a ridiculous false story by an unknown start-up app/website to garner some attention for itself, with no regard to actually being factual."

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When Vanity Fair's long-awaited Gwyneth Paltrow expose arrived with an underwhelming whimper, Paltrow fans and haters alike wondered if there might be more hidden scandals that didn't make it to print.

This morning, a new secret-sharing app called Whisper claimed to have uncovered a secret that Graydon Carter wouldn't touch -- that Paltrow was cheating on husband Chris Martin with entertainment lawyer Kevin Yorn. Reps for Paltrow were quick to slam the rumor, and claim they're getting lawyers involved.

Paltrow's publicist Stephen Huvane said the report is "absolutely 100 percent false. The (source) at Whisper is clearly a fake. … This is clearly a fabricated story with no credibility at all."