At the heart of the Cambridge Analytica data scandal is an app that gathered users’ info from a series of light-hearted questions. And Facebook is full of these pages, asking users seemingly-innocuous questions like what was users’ first jobs, childhood pets, high school and more. There’s nothing wrong with this kind of curiosity on the surface, but it’s also true that questions like this are often used as a security protocol to access sensitive accounts.

Investigative reporter Brian Krebs pointed out this problem on a post for his blog, Krebs on Security. In one example Krebs cites, he found the Facebook page for a tire and repair shop that asked users “what car did you learn to drive stick shift on?” For many people, that will be the same answer as “what was your first car?”, which is often used as a security question.

“On the surface, these simple questions may be little more than an attempt at online engagement by otherwise well-meaning companies and individuals,” Krebs wrote. “Nevertheless, your answers to these questions may live in perpetuity online, giving identity thieves and scammers ample ammunition to start gaining backdoor access to your various online accounts.”

In case the avalanche of recent negative news stories didn’t convince you it’s a good idea to share less on Facebook, this blog further reinforces the importance of keeping your private info to yourself.