While speaking to E!'s Seacrest on the red carpet before the awards show, Baron Cohen - appearing as his Dictator character General Aladeen - spilt a golden urn containing the 'ashes of the late dictator Kim Jong-il' onto the presenter.
Talking on his KIIS-FM show following the 84th Academy Awards, Seacrest revealed that he became suspicious of Cohen since their interview was going "too normally".
"I definitely did not know that he was going to do that," he explained. "He comes over, and I asked him a couple of questions, but, you know that feeling in your gut. You feel like, 'This is going too normally'.
"I saw the urn coming up. It was getting closer to my chest, and then it tipped over, and it wasn't the wind. He spilt it on my tuxedo."
Seacrest added that he was able to get through the evening following the incident thanks to advice from his mother, who told him to "always make sure to bring two jackets, because you never know what's going to happen".
Several stars reacted to the incident, with Piers Morgan saying that the stunt was "not funny".
More Oscars coverage:
> Oscars 2012: 'The Artist', 'Hugo' win five Academy Awards
> Oscars: 'The Artist' wins 'Best Picture' Academy Award
> Oscars: Meryl Streep pays tribute to friends in 'Best Actress' speech
> Oscars 2012: 84th Academy Awards live blog
> Oscars 2012: Academy Awards winners list in full
> Oscars: Academy Awards 2012: Red carpet pictures
Listen to Ryan Seacrest talk about the Oscars 2012 below: