The complete source code for the Android remote access Trojan (RAT) called Dendroid has been leaked online, which researchers have found contains several vulnerabilities.
The existence of Dendroid (Android.Dendoroid) was first reported by Symantec in March when the threat was causing a buzz on underground forums. Dendroid is a HTTP RAT that has a complex control panel and an APK binder that allows cybercriminals to repackage and trojanize legitimate Android apps with the malware.
The Trojan was sold for a one-time fee of $300, for which customers got features that enabled them to delete call logs, call specified phone numbers, open websites, record calls and audio, intercept messages, open applications, initiate denial-of-service (DoS) attacks, take pictures and record video. In addition, the seller promised 24/7 support.
The source code for Dendroid, its control panel, the APK binder and updates for bug fixes were put up for sale on hacker forums in late July. It was initially sold for 1 Bitcoin, but the seller later made a 50% discount. The code was then leaked on Friday to GitHub and is accompanied by a "readme" file that provides a list of requirements needed to run the threat, along with instructions on how to set it up.
After examining the source code, researchers from PhishLabs found multiple vulnerabilities caused by the lack of user input validation. They have identified cross-site scripting (XSS), SQL injection, arbitrary file upload, and PHP code execution flaws.
"The lack of user input validation in Dendroid's control panel is severe, especially when you consider the level of operational security needed in even smaller crimeware campaigns," PhishLabs Threat Analyst Paul Burbage explained in a blog post.
One of the vulnerabilities, for which PhishLabs has published a proof-of-concept, is an unsanitized user input written to a file called Panel/config.php via a POST request to Panel/applysettings.php. By rewriting the configuration file, an attacker can inject and execute arbitrary PHP code, and even make the control panel inoperable.
This isn't the only piece of malware which had its source code was put up for sale recently. In May, malware authors began advertising the source code for version 2.0 of the information-stealing Trojan Pony Loader (Fareit).
"In the past, malware source code leaks have spawned several variants and led to more widespread use of the crimeware features that made the original malware desirable," Burbage explained. "When the source code for Zeus Trojan was leaked in 2011, for example, it accelerated the proliferation of features designed to bypass online banking security measures."
While Dendroid is in a different league than Zeus, the expert believes that the leaked code will most likely result in the widespread use of the Android RAT and its future variants.