Design of SMS Commanded-and-Controlled and P2P-Structured Mobile Botnets Yuanyuan Zeng, Kang G. Shin, Xin Hu The University of Michigan, Ann Arbor, MI 48109-2121, U.S.A. fgracez, kgshin,
[email protected] Abstract—Botnets have become one of the most serious security is usually capable of only one or two functions. Although the threats to the Internet and personal computer (PC) users. number of mobile malware families and their variants has been Although botnets have not yet caused major outbreaks in mobile growing steadily over the recent years, their functionalities networks, with the rapidly-growing popularity of smartphones such as Apple’s iPhone and Android-based phones that store have remained simple until recently. more personal data and gain more capabilities than earlier- SymbOS.Exy.A trojan [2] was discovered in February 2009 generation handsets, botnets are expected to move towards this and its variant SymbOS.Exy.C resurfaced in July 2009. This mobile domain. Since SMS is ubiquitous to every phone and can mobile worm, which is said to have “botnet-esque” behavior delay message delivery for offline phones, it is a suitable medium patterns, differs from other mobile malware because after for command and control (C&C). In this paper, we describe how a mobile botnet can be built by utilizing SMS messages infection, it connects back to a malicious HTTP server and for C&C, and how different P2P structures can be exploited reports information of the device and its user. The Ikee.B for mobile botnets. Our simulation results demonstrate that a worm [3] targets jailbroken iPhones, and has behavior similar modified Kademlia—a structured architecture—is a better choice to SymbOS.Exy.