Sharkbot Malware Found In Several Android Antivirus Apps

If you own an Android device, odds are excellent that your go-to source for apps of any kind is the Google Play Store.  That includes antivirus apps to help keep your device safe.

Unfortunately, the hackers of the world are aware of that fact and are always on the lookout for ways to capitalize on that.

Recently, researchers at Check Point have made a disturbing discovery.  Six different apps on the Play Store were recently found to be poisoned variants containing the Sharkbot malware. Sharkbot is designed to steal usernames and passwords by displaying cleverly disguised overlay windows that appear over the login window you expect to see when you visit a given website.

Instead of entering your login credentials on the site you thought you were visiting, you instead inadvertently feed the credentials to the bot. The bot dutifully exfiltrates them to a command-and-control server so the hackers controlling the malicious code can abuse them at their leisure.

To add insult to injury, all six of the poisoned apps appeared to be perfectly legitimate antivirus apps. Even worse is those apps were downloaded by unsuspecting users more than fifteen thousand times before Google caught the issue and removed them from the Play store.

Alexander Chailytlko is the cyber security researcher who led the team that made the discovery. They have an intriguing theory about how the hackers were able to get their poisoned code past Google’s robust series of checks against exactly such things.

Per Chailytko, “We think that they were able to do it because all malicious actions were triggered from the C&C server, so the app could stay in the “OFF”-state during a test period in Google Play and turn “ON” when they get to the users’ devices.”

If that theory proves correct and there’s little reason to doubt it  Google is going to have a tough time keeping that sort of thing from happening in the future. That means the Play Store may not be quite the safe place most people expect.  That’s troubling indeed.