Man-in-the-middle (MITM) attacks are “wreaking havoc” on Android users because over two-thirds of the most popular apps on Google Play contain SSL vulnerabilities, according to new research from FireEye.
After being notified by the security vendor, the developers of said apps have now addressed the vulnerabilities, but the study nevertheless highlights the ongoing security problems with the Google ecosystem.
MITM attacks occur when hackers intercept data sent by an app to a server or vice versa, either to look at the data itself; to replace it with malicious data which injects itself into the app; or redirect traffic to a new destination controlled by the attacker.
FireEye mobile threat researchers Adrian Mettler, Vishwanath Raman and Yulong Zhang explained in a blog post that they examined the 1,000 most downloaded free apps on Google Play only to find 674 (68%) had at last one of three particular SSL vulnerabilities.
Of the 614 apps that use SSL/TLS to communicate with a remote server, 73% didn’t check server certificates at all, exposing any data they exchange with those servers to potential theft.
In addition, around 8% of those 614 used their own hostname verifiers which don’t check hostnames, “implying they are incapable of detecting redirection attacks where the attacker redirects the server request to a malicious webserver controlled by the attacker.”
Finally, 77% ignored SSL errors generated when they use Webkit to render server pages, which means they could be missing MITM attacks that exploit vulnerabilities like Javascript Binding Over HTTP (JBOH), FireEye said.
The researchers carried out a similar study on a random sample of 10,000 free Android apps available on Google Play and found 40% used trust managers that don’t check server certs; 7% used hostname verifiers that don’t check hostnames; and 13% didn’t check SSL errors when using Webkit.
Among the apps found wanting were Camera360 Ultimate, which has 250 million downloads worldwide.
“Besides inheriting SSL vulnerabilities from the ad libraries used by the application, none of the application’s trust managers uses check server certificates,” FireEye noted.
“In another proof-of-concept for an MITM attack that exploits these vulnerabilities, we intercepted all HTTPS traffic between the application and the remote servers it used, allowing us to potentially: Steal or inject photos/albums at random; steal users’ login ‘local key’ to the Camera360 cloud, and many other local device/user specifications; and intercept user credentials or inject fake login pages/malicious Javascript to steal any account credentials.”
According to Trend Micro, malicious Android apps hit the two million milestone in March this year just six months after passing the one million mark.