Targeted Deanonymization via the Cache Side Channel: Attacks and Defenses
Side-channel techniques have been traditionally applied toward the recovery of computer-related secrets, such as cryptographic keys. Recently, however, attackers have turned to target humans, who also share secrets of their own with their computers. Recoverable human secrets include, for example, browsing habits, keystrokes, political or religious beliefs, or sensitive information about the user's health. In this talk, I will show how a cache side-channel attacker can target humans using a *targeted deanonymization* attack. Targeted deanonymization attacks, which let a malicious website discover whether a website visitor bears a certain public identifier, such as an email address or a Twitter handle, are both practical and dangerous, as they can put journalists, activists, and other vulnerable populations into serious risk.
After describing and demonstrating the attack, I will talk about the unique challenge of defending against an attack which involves users, and show how mitigations against the attack were built into the popular NoScript extension.
Based on joint work with Mojtaba Zaheri and Reza Curtmola presented at USENIX Security ’22. Artifacts available here: https://github.com/leakuidatorplusteam/artifacts
Yossi Oren is a Senior Lecturer (Assistant Professor in U.S. terms) in the Department of Software and Information Systems Engineering at Ben Gurion University of the Negev, and a member of BGU's Cyber Security Research Center. Prior to joining BGU, Yossi was a Post-Doctoral Research Scientist in the Network Security Lab at Columbia University in the City of New York and a member of the security lab at Samsung Research Israel. He holds a Ph.D. in Electrical Engineering from Tel-Aviv University (thesis), and an M.Sc. in Computer Science from the Weizmann Institute of Science (thesis). His research interests include implementation security (side-channel attacks, micro-architectural attacks, power analysis and other hardware attacks and countermeasures; low-resource cryptographic constructions for lightweight computers) and cryptography in the real world (consumer and voter privacy in the digital era; web application security). He has been recognized by The Register as a Top Boffin.
Photo copyright: Ben-Gurion University of the Negev.