What a 'cock up!': Can you spot what's hilariously wrong with this photo?

A festival-goer learned the hard way that a seemingly innocent photograph of herself in fact hid a very rude optical illusion. Photo / Caters

A festival-goer learned the hard way that a seemingly innocent photograph of herself in fact hid a very rude optical illusion.

New mum Hailee Bridge, 38, was hanging out at Big Day Out festival on the Gold Coast when she posed for the double-take snapshot three years ago.

But when she recently uploaded it to social media, friends lost no time in pointing out the unfortunate timing – which made it look like she'd grown a male body part.

Because in a cruel twist of fate, it appears as if the leg of a fellow audience member is actually Hailee's penis – and the cock up was much to the amusement of many.

Despite noticing the X-rated impression when she first uploaded it, Hailee still tried to fly under the radar – only to be shafted by her giggling Facebook friends.

Hailee, who recently gave birth to her first child, said: "I was having a great time there and of course I didn't notice anything at the time.

"It wasn't until I put it online that I thought 'oh my god, hang on?'. But in the end I just decided 'it's a good pic of me so hopefully nobody says anything'!"

Photo / Caters

"It got a reaction straight away. One friend was like 'put it away Hails!' and another said 'you've kept a big secret Hailee, that thing is so big you couldn't hold it up with sticky tape!'."

"It was a bit annoying, but I'm glad people got a kick out of it. If I can make people laugh it's a good day."

The image is the latest in a long line of optical illusions to set the internet on fire.

Whether you put it down to a trick of the eye or a dirty mind, it's safe to say the innocent yet seemingly lewd pictures make for some priceless entertainment.

In hindsight, Hailee admitted she doesn't know how she thought the photo-fail would go unnoticed.

She added: "At the time I was like 'nah, no one will notice.' When I look at it now I don't know why I thought I could away with it!

"I was just bummed because I thought it was a good picture of me! That was the only bad thing about it."

- By Caters