Yarin Perry (The Hebrew University of Jerusalem), Neta Rozen-Schiff (The Hebrew University of Jerusalem), Michael Schapira (The Hebrew University of Jerusalem)

The Network Time Protocol (NTP) synchronizes time across computer systems over the Internet and plays a crucial role in guaranteeing the correctness and security of many Internet applications. Unfortunately, NTP is vulnerable to so called time shifting attacks. This has motivated proposals and standardization efforts for authenticating NTP communications and for securing NTP textit{clients}. We observe, however, that, even with such solutions in place, NTP remains highly exposed to attacks by malicious textit{timeservers}. We explore the implications for time computation of two attack strategies: (1) compromising textit{existing} NTP timeservers, and (2) injecting textit{new} timeservers into the NTP timeserver pool. We first show that by gaining control over fairly few existing timeservers, an textit{opportunistic} attacker can shift time at state-level or even continent-level scale. We then demonstrate that injecting new timeservers with disproportionate influence into the NTP timeserver pool is alarmingly simple, and can be leveraged for launching both large-scale textit{opportunistic} attacks, and strategic, textit{targeted} attacks. We discuss a promising approach for mitigating such attacks.

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Screen Gleaning: A Screen Reading TEMPEST Attack on Mobile...

Zhuoran Liu (Radboud university), Niels Samwel (Radboud University), Léo Weissbart (Radboud University), Zhengyu Zhao (Radboud University), Dirk Lauret (Radboud University), Lejla Batina (Radboud University), Martha Larson (Radboud University)

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Bitcontracts: Supporting Smart Contracts in Legacy Blockchains

Karl Wüst (ETH Zurich), Loris Diana (ETH Zurich), Kari Kostiainen (ETH Zurich), Ghassan Karame (NEC Labs), Sinisa Matetic (ETH Zurich), Srdjan Capkun (ETH Zurich)

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Detecting Tor Bridge from Sampled Traffic in Backbone Networks

Hua Wu (School of Cyber Science & Engineering and Key Laboratory of Computer Network and Information Integration Southeast University, Ministry of Education, Jiangsu Nanjing, Purple Mountain Laboratories for Network and Communication Security (Nanjing, Jiangsu)), Shuyi Guo, Guang Cheng, Xiaoyan Hu (School of Cyber Science & Engineering and Key Laboratory of Computer Network and Information Integration…

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V2X Security: Status and Open Challenges

Jonathan Petit (Director Of Engineering at Qualcomm Technologies) Dr. Jonathan Petit is Director of Engineering at Qualcomm Technologies, Inc., where he leads research in security of connected and automated vehicles (CAV). His team works on designing security solutions, but also develops tools for automotive penetration testing and builds prototypes. His recent work on misbehavior protection…

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