The former TOWIE star, 28, shared a sexy snap with fans last week, showing a glam woman baring her backside while straddling a stool.
Eagle-eyed viewers soon realised the picture was actually of glamorous US model Carmen Ortega, who was none too happy to see her image on Lauren's page.
Carmen had posted the original photo, showing off her fabulous booty, to her Instagram account before a version appeared on Lauren's own account. Fans believed the image on Lauren's account was altered to make the woman's behind look wider.
It was later removed from Lauren's account.
Speaking in today's issue of The Sun, 27-year-old Carmen expressed her anger at the situation, accusing Lauren of altering her original image and being an "imposter". She also said she wanted Lauren to publicly apologise.
"I feel violated. I honestly feel sad that she would be so desperate to do such a thing. I work really hard on my body and looks, and my modelling career is on the rise because of my hard work," she added.
Carmen suggested she is now speaking with a lawyer.
Lauren has now responded – indirectly – via an Instagram post, saying: "As soon as you put a picture out there online you lose control of that image.
"I have this with images all over the internet and people use them for malicious postings. Personally, I would never do that. The only time I ever use images that are not mine is for inspiration or motivation. Namaste."
Carmen has yet to reply.
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