Tyga's Cannes Chick Demi Rose: I'm Not a Hooker!

Tyga's smoking hot rebound chick, Demi Rose, says she's fallen victim to prostitute identity theft -- since her face and bod are all over high-priced escort websites.

Demi's got quite the Instagram portfolio and ever since she was seen with Tyga in Cannes ... pics from her page have been popping up on sites hawking companionship all over the globe -- from the U.S. to Dubai.

She tells TMZ ... don't believe the hype, since she's never done any sort of escorting and doesn't want her name associated with it.

Demi, who's a model by trade, says she's seen this happen to lots of girls in her biz ... and she's considering legal action.