Just forget the Facebook Security Breach, there is a latest WhatsApp Spyware which can access personal files on your phone.
WhatsApp is now accessing user's personal data available on the device, apart from chats. Seeing the popularity of WhatsApp and also the fact that it is now owned by Facebook, makes it one of the prime target for hackers who basically try to spread spyware and other malicious apps.
The spyware will not just access users chats but also other elements in the app and also on the device. However, the spyware seems to be under the development stage and was spotted in an open development project online.