If cameras steal our souls, then the Internet sells them. I’m talking about Google Images sharing my fifth-grade class picture, among other humiliations. When images post—however, wherever and in spite of privacy settings and site agreements—they can be vulnerable to public outing and even repurposing without our knowledge.

A sad example is 19-year-old lingerie model Kara Nichols, who’s been missing from her Colorado town since early October. When her face was discovered on a Vegas escort site, authorities thought she might be here, but it turns out the portraits were used sans her permission. “In speaking with authorities from the Las Vegas area, they say that it’s quite common for escort businesses to simply shop around on the Internet and find photos like that,” Lt. Jeff Kramer of the El Paso County Sheriff’s Office told Colorado news station KRDO.

Most images are automatically copyrighted the moment they’re created. Others are in the public domain. The problem? Most of us assume, or pretend to assume, that the entire webiverse is public domain.

“The question is, does it just become public domain by virtue of being posted on Facebook? Of course not,” writes Chip Stewart of the Texas Center for Community Journalism. He adds, though, that suing for invasion of privacy probably isn’t an option. “It’s a bit like … putting out your photos on the coffee table—you give up your right to claim intrusion when you invite public people to see them.”

Unless you live in China, don’t count on the Internet police. Instead, be wary of public people. And Google. And especially yourself.