Justin Bieber made jaws drop recently after he posted a photo of his bare butt on Instagram. It's not every day that a celebrity shows off their backside on social media. Though, it definitely happens more than you'd think. Everyone from Kendall Jenner to Cody Simpson have bared it all online!

Click through the gallery to see the most scandalous celeb photos of all time, then let us know whose pic shocks you the most in the comments below.