The Ben Gurion University security researchers who tangled with Samsung over its KitKat security implementation have posted a follow-up, in which they demonstrate how a malicious app could bypass some VPN protections in Android.
Back in December, the university's Cyber Security Labs stated that Samsung's Knox implementation was insecure, but last week the mobe-maker and Google agreed that the problem lies in Android rather than being specific to one handset vendor.
The researchers now say that in a related vulnerability, they have used a malicious app to redirect a user's VPN connection to a server which is then able to capture user traffic. As the researchers state:
“This vulnerability enables malicious apps to bypass active VPN configuration (no ROOT permissions required) and redirect secure data communications to a different network address. These communications are captured in CLEAR TEXT (no encryption), leaving the information completely exposed. This redirection can take place while leaving the user completely oblivious, believing the data is encrypted and secure.”
The vulnerability is demonstrated in the video below.
The researchers haven't published the code for their exploit, but say they have notified Google of the vulnerability and will provide more detail once the problem has been patched.
While the vulnerability provides deep access to user communications that are supposed to be protected, it's important to note that it can only be exploited if a user can be tricked into installing a malicious application.
Also, SSL / TLS traffic remains encrypted: it can be captured, but not in plain text.
At this stage, the researchers have only tested their attack on Android 4.3 KitKat. ®