Viber has fixed a security glitch in its instant messenger application that reportedly allowed unauthorised users to bypass screen locks, and obtain control of a smartphone installed with the application.
Discovered by Vietnamese security firm Bkav, the attack revolved around delivering multiple messages to a victim via Viber.
According to the firm, smartphones developed by Samsung, Sony and HTC were vulnerable to attack.
Bkav Security Division director Nguyen Minh Duc said: "The way Viber handles to popup its messages on smartphones’ lock screen is unusual, resulting in its failure to control programming logic, causing the flaw to appear."
The flaw allowed an unauthorised user to gain access by performing a few actions on Viber new message popups, combining some tricks such as using victim’s notification bar and sending other Viber messages.
Bkav claimed that more than 50 million smartphone users worldwide are facing a risk posed by the critical flaw in Viber.
The free Viber app works similar to Skype and allows Android device users to send messages and speak for free.
