A new piece of malware is trying to take advantage of Skype's increasing popularity, especially on mobile devices. Cybercriminals have created a fake version of the Skype for Android app, designed to earn money from unsuspecting users. Trend Micro, which first discovered the malware, is calling this particular threat JAVA_SMSSEND.AB.
The Java in the name should not surprise you, given that Android apps are primarily developed in a custom version of the programming language. Thankfully, this is not a very good fake. The app in question only runs on older (pre Software Installation Script) Symbian phones or Android devices that allow execution of Java MIDlet.
The cybercriminals behind this scheme have set up fake websites advertising fake Skype apps. Most of the sites are hosted on Russian domains (.ru) but the fake apps themselves are hosted on Nigerien domains (.ne).
The reason this is not a good fake is that instead of an .apk file (the expected package file for Android apps), users are served up with a .jar (Java MIDlet). While the app poses as an installer for Skype, what it really does is install a piece of malware. The devil is in the details: in the background, the malicious app sends expensive international text messages to earn its creators revenue.