Apple's AirDrop feature is a convenient way to share things, but it can also pose a privacy risk.

A recently discovered AirDrop flaw lets strangers see your phone number and email address simply by opening an iOS or macOS share sheet within other people’s Wi-Fi range. It’s one of several privacy vulnerabilities that Mac and iOS users need to be aware of.

“Our iOS devices are connected to countless social media apps, third-party messaging platforms, and networking sites that allow people to share all kinds of content with each other,” Hank Schless, a security expert at cybersecurity firm Lookout, said in an email interview. “If you receive a file from an unknown contact, you should always consider it potentially dangerous until proven otherwise.”

The flaws in AirDrop’s security protocols were reportedly discovered by researchers in 2019, who alerted Apple to the issue. However, the company has yet to provide a fix. A recent report concluded that the issue is more extensive than previously known.