X Factor judge Contostavlos recently featured in a leaked sex tape with her ex-boyfriend MC Ultra filmed several years ago.
> Britain's Got Talent: The six best auditions so far - videos
> Tulisa Contostavlos: 'Cheryl Cole sent me text after sex tape scandal'
Britain's Got Talent judge Holden said that her co-star Alesha Dixon sent her a link to the clip in order to watch it.
"It's a terrible thing to confess, but everyone wants to see it. It was her," she told Alan Carr on his talkshow Chatty Man.
When Carr suggested that the clip might not have featured the singer and may have used green screen trickery, Holden replied: "I've had a green screen where I've had to fall off the end of a cliff - but never one with a ****".
Holden was joined on the chatshow by fellow Britain's Got Talent judge David Walliams, who joked that he has a crush on Simon Cowell.
"He's a very attractive man. He won't let me in the back of his Bentley," Walliams quipped.
The pair will appear on Chatty Man tonight (Friday, April 4) at 10pm on Channel 4.