I'm working on securing apps from malware attack in project. I just want to know how app is repackaged with malware. Because for reverse engg. we've apktool, dex2jar, Java decompiler. But how intruders change code in java and then repackage it. Because I think it is not possible to get jar to dex. Please help.
closed as not a real question by Rook, Gilles, Terry Chia, AJ Henderson, Iszi Apr 9 '13 at 14:21
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There is a wealth of information on cracking android apps or more generally patching java bytecode. Adding malware to an app is a very similar process to removing some naive client side security check.