Nick Hogan -- I Erased Underage Pics ... Juuust In Case

Nick Hogan's hacked nude photos of girls he dated in high school ... were a huge wake up call to instantly trash the images because, technically, they're now child porn -- and Nick had no idea they still existed.

The pics were taken when Hogan was in high school and even though he and the women in the photos were the same age at the time ... Nick didn't want people -- and cops -- thinking he was in possession of illegal images.

In fact, Nick didn't even know the computer with the pics was connected to the cloud, because it's been in storage for years. As we first told you ... the hackers also snatched shots of Nick's mom in a thong. Super creepy, but not illegal.