  This paper presents a measurement study of information leakage and SSL
vulnerabilities in popular Android apps. We perform static and dynamic analysis
on 100 apps, downloaded at least 10M times, that request full network access.
Our experiments show that, although prior work has drawn a lot of attention to
SSL implementations on mobile platforms, several popular apps (32/100) accept
all certificates and all hostnames, and four actually transmit sensitive data
unencrypted. We set up an experimental testbed simulating man-in-the-middle
attacks and find that many apps (up to 91% when the adversary has a certificate
installed on the victim's device) are vulnerable, allowing the attacker to
access sensitive information, including credentials, files, personal details,
and credit card numbers. Finally, we provide a few recommendations to app
developers and highlight several open research problems.
