A sex video with the telly babe’s head superimposed on to the body of a porn actress was being shown on an adult movie site.
The fake material is threatening to ruin Cheryl's family-friendly image and has left her management team furious.
But almost a million fans have already seen the shock footage. People with accounts on XXX site Pornhub cashed in on her fame by using her name in a string of videos.
One clip even has a picture of her face Photoshopped on to the body of a naked porn babe under the title "Cheryl Cole fake sex video".
Sources close to Cheryl, 32, fear some fans might think it is leaked footage of her having sex.
Another video boasts it includes a performer who looks just like pop babe Cheryl – using her former surname Cole.
It lasts for more than ten minutes and had last night racked up more than 800,000 views.
The tag line teases users, saying: "Watch Cheryl Cole lookalike get f*****."
X Factor bosses are also worried it could take months to get the clips removed from the internet – or even prove impossible.
Pornhub is free to use but its owners are able to cash in on videos via lucrative advertising deals which will earn more depending on the number of video views.
A source close to Cheryl said on Saturday: "She hates the fact the porn site is using her name to drag punters in to watch their lurid videos and make money from her fame.
"It is embarrassing for her to be linked to this kind of video because she works very hard to cultivate her image."
A spokesman for Cheryl said last night: "Our lawyers are looking into this."
Cheryl was back on telly last night alongside new co-star Rita Ora, 24, for the first instalment of X Factor auditions.
Viewers saw both Rita and show boss Simon Cowell, 55, call Cheryl by ex Ashley Cole’s surname instead of her new married name.
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