Visible to the public Biblio

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Kolias, Constantinos, Copi, Lucas, Zhang, Fengwei, Stavrou, Angelos.  2017.  Breaking BLE Beacons For Fun But Mostly Profit. Proceedings of the 10th European Workshop on Systems Security. :4:1–4:6.
Bluetooth Low Energy (BLE) Beacons introduced a novel technology that enables devices to advertise their presence in an area by constantly broadcasting a static unique identifier. The aim was to enhance services with location and context awareness. Although the hardware components of typical BLE Beacons systems are able to support adequate cryptography, the design and implementation of most publicly available BLE Beacon protocols appears to render them vulnerable to a plethora of attacks. Indeed, in this paper, we were able to perform user tracking, user behavior monitoring, spoofing as well as denial of service (DoS) of many supported services. Our aim is to show that these attacks stem from design flaws of the underlying protocols and assumptions made for the BLE beacons protocols. Using a clearly defined threat model, we provide a formal analysis of the adversarial capabilities and requirements and the attack impact on security and privacy for the end-user. Contrary to popular belief, BLE technology can be exploited even by low-skilled adversaries leading to exposure of user information. To demonstrate our attacks in practice, we selected Apple's iBeacon technology, as a case study. However, our analysis can be easily generalized to other BLE Beacon technologies.
Guan, Le, Jia, Shijie, Chen, Bo, Zhang, Fengwei, Luo, Bo, Lin, Jingqiang, Liu, Peng, Xing, Xinyu, Xia, Luning.  2017.  Supporting Transparent Snapshot for Bare-metal Malware Analysis on Mobile Devices. Proceedings of the 33rd Annual Computer Security Applications Conference. :339–349.

The increasing growth of cybercrimes targeting mobile devices urges an efficient malware analysis platform. With the emergence of evasive malware, which is capable of detecting that it is being analyzed in virtualized environments, bare-metal analysis has become the definitive resort. Existing works mainly focus on extracting the malicious behaviors exposed during bare-metal analysis. However, after malware analysis, it is equally important to quickly restore the system to a clean state to examine the next sample. Unfortunately, state-of-the-art solutions on mobile platforms can only restore the disk, and require a time-consuming system reboot. In addition, all of the existing works require some in-guest components to assist the restoration. Therefore, a kernel-level malware is still able to detect the presence of the in-guest components. We propose Bolt, a transparent restoration mechanism for bare-metal analysis on mobile platform without rebooting. Bolt achieves a reboot-less restoration by simultaneously making a snapshot for both the physical memory and the disk. Memory snapshot is enabled by an isolated operating system (BoltOS) in the ARM TrustZone secure world, and disk snapshot is accomplished by a piece of customized firmware (BoltFTL) for flash-based block devices. Because both the BoltOS and the BoltFTL are isolated from the guest system, even kernel-level malware cannot interfere with the restoration. More importantly, Bolt does not require any modifications into the guest system. As such, Bolt is the first that simultaneously achieves efficiency, isolation, and stealthiness to recover from infection due to malware execution. We have implemented a Bolt prototype working with the Android OS. Experimental results show that Bolt can restore the guest system to a clean state in only 2.80 seconds.