Just when you thought WhatsApp was safe... not so fast.
A new flaw was found in the Android version of WhatsApp that allows other apps to reach in and see your conversations. The vulnerability was found by Bas Bosschert, the CTO at DoubleThink, who explained the method with a step-by-step guide on his blog. Because WhatsApp for Android stores its files of the phone's SD card, any other app that has full access to the SD card (which is common) would be able to gain access to the user's conversations. Bosschert built a dummy app to try it out, and was able to extract conversations from the messaging service. His dummy app could have duped a potential user by distracting them with a loading screen while it took the information.
As TechCrunch points out, this is more a problem with Andoid than it is with WhatsApp. Apple's iOS doesn't allow for apps to gain access to other information as Android allows, which is why this isn't a problem for the iOS version of WhatsApp.