Business Insider
Quartz reports that developers discovered a security flaw that reveals username's phone numbers.
The vulnerability was found to involve the way the app sends messages to its users, taking advantage of an infrastructure issue that leaves the database of user phone numbers open to anyone capable of sending a request for the information.
Developers concerned over just how easy it was to access user information took to Twitter to discuss the issue, even creating the hashtag #YoBeenHacked.
Developers even used the app's vulnerability to send out an announcement and warning of the security flaws.
Yo creator Or Arbel admitted to TechCrunch that the app did have some security issues, saying that the team was "taking this very seriously."
For those wanting to take precaution, deleting the app until a full fix and update has been added might not be a bad idea.
You can read our full interview with Yo's creator here.