(CNN) Shubnum Khan's face has appeared in McDonald's ads in China, India and South Korea, on a French dating website and in a promotion for a trek in Cambodia.

Friends have spotted her on food advertisements, banking brochures, eye clinics and, more commonly, on makeup websites testifying to the efficacy of products she has never used.

However, Khan is not an international model, nor did she receive any payment for the various global commercial campaigns she appeared in. Khan's is a cautionary tale of the snap decisions we make that can come back to haunt us in often unexpected ways.

Again, the face of positive immigration in Uruguay. (TBH I don't really mind the ads promoting immigration). pic.twitter.com/6JGr1cArhX

As a student, Khan unwittingly signed away the rights to her image in exchange for free prints during a photo shoot.

Those pictures ended up as stock images, used commercially all over the world in campaigns and fake product testimonials.

Khan recounted how she first discovered her image was used in a campaign six years ago, in a now-viral Twitter thread she posted to warn others about taking care to read the small print on contracts.

She said she thought nothing of the agreement with the photographer until a friend alerted her to a Facebook post in 2012, where her face was being used to promote immigration in Canada.

So today I'm going to tell you the story of How I Ended Up with my Face On a McDonald's Advert in China - A Cautionary Tale. Six or so years ago, a friend in Canada posted a pic on my FB wall to say she found an advert of me promoting immigration in a Canadian newspaper. pic.twitter.com/QJ0nWpYNmQ — Shubnum Khan (@ShubnumKhan) July 28, 2018

"That's when I started to do some research and found the images online," she told CNN via email.

"Naturally I was shocked and ... confused. I studied the pic and agreed that it was me. Now, I didn't mind that I was promoting immigration in Canada, but I couldn't understand why my face was in a paper all the way on that side of the world," Khan said.

Over the years, her face would pop up randomly and in countries from America to China, selling products in ads, billboards, magazines.

She said she has no idea how many countries her ads have appeared in.

One of the adverts showing Shubnum Khan.

"I have heard about adverts in South Africa, (the) USA, London, China, India, Brazil, Uruguay, Canada and Kenya and then I guess you can't really put a country to the adverts online," she said.

Khan said she contacted the photographer, who reminded her of the agreement.

He told her he sold the photos to companies specializing in stock images and warned that they may still appear in unusual places, although he has said he will take her images down.

However, Khan says she has no hard feelings towards the photographer and blamed herself for not reading the small print. "Look, at the end of the day, I signed the document without reading it. I don't agree with the way things were done to us, but I know I have myself to blame in this situation."

"I thought it was to give him permission to use the photos for his portfolio. We didn't read the small print. I know. It was stupid," Khan, who lives in Durban, South Africa said.

Khan, an author who is working on her second novel , said she was amused to see that her nationality became fluid depending on the nature of the advertising campaign.

I can also take on new identities. The most shocking of these are adverts to teach & care for kids - so who is actually with the kids? When I asked the photographer abt this, he says I signed away rights to 'distortion of character including false names'. pic.twitter.com/2MzIZPAfi5 — Shubnum Khan (@ShubnumKhan) July 28, 2018

But the most shocking aspect of it for her were the companies who claimed she had used their products. Khan said it is laughable when people share stories of how her fake testimonials had inspired them.

"I didn't know it was legal to give fake testimonials in any way or form. It really made me realize how much we are lied to as consumers. I'm wondering about the dating website one. Like, who do people actually meet at the end of the day, then?

"For me, that was quite unbelievable. Like I don't know how you get away with that one."

"The most shocking of these are adverts to teach and care for kids -- so who is actually with the kids? When I asked the photographer about this, he says I signed away rights to 'distortion of character including false names,' " she said.

She said she's surprised at how big the story has become since sharing it on Twitter.

"I didn't expect that at all. I knew it was a strange story but I thought people wouldn't get too surprised that things like this happen. I'm glad we can still feel surprised and compassionate about situations like this."

Khan says she is aware of the error of judgment and hopes her story will serve as a warning to others.

"Read what you sign, don't get caught in any hype. When you think, 'oh, I'm not reading this or I don't understand it, but what's the worst that can happen?' "

"I think my example is one of the things that can happen."