► VIDEO | To Err.Is Human: Characterizing the Threat of Unintended URLs in Social Media

VIDEO | February 12, 2021, 12 pm EDT

Beliz Kaleli
Ph.D. Researcher, Boston University


To make their services more user friendly, online social media platforms automatically identify text that corresponds to URLs and render it as clickable links. In this paper, we show that the techniques used by such services to recognize URLs are often too permissive and can result in unintended URLs being displayed in social network messages. Among others, we show that popular platforms (such as Twitter) will render text as a clickable URL if a user forgets a space after a full stop at the end of a sentence, and the first word of the next sentence happens to be a valid Top Level Domain. Attackers can take advantage of these unintended URLs by registering the corresponding domains and exposing millions of Twitter users to arbitrary malicious content. To characterize the threat that unintended URLs pose to social media users, we perform a large-scale study of unintended URLs in tweets over a period of 7 months. By designing a classifier capable of differentiating between intended and unintended URLs posted in tweets, we find more than 26K unintended URLs posted by accounts with tens of millions of followers. As part of our study, we also register 45 unintended domains and quantify the traffic that attackers can get by merely registering the right domains at the right time. Finally, due to the severity of our findings, we propose a lightweight browser extension that can, on the fly, analyze the tweets that users compose and alert them of potentially unintended URLs and raise a warning, allowing users to fix their mistakes before the tweet is posted.

Speaker Bio

Beliz graduated from the Electrical and Electronics Engineering school of Middle East Technical University. After a year in the industry as a software engineer, she began pursuing her Ph.D. at Boston University. Beliz is currently in her sixth semester and has published three papers in the area of web security. Since declaring cybersecurity as her area of interest she has worked closely with Dr. Manuel Egele and Dr. Gianluca Stringhini in their security lab, (SeclaBU) at Boston University.

► VIDEO | Foundations of Blockchain Systems

VIDEO | February 11, 2021, 12 pm EDT |

Julian Loss
University of Maryland

Abstract: One of the most successful applications of modern cryptography has been its use in electronic and digital payment systems. In traditional systems, a trusted authority handles all payments (e.g., a bank or a credit card company). More recently, blockchain systems have emerged as a trust-free and increasingly popular alternative.

In a blockchain system, users jointly emulate the trusted authority by running a distributed protocol to agree on the transaction history of users (i.e., the blockchain). Making blockchain systems a secure and scalable environment poses many new and fascinating challenges that require solutions from both cryptography and distributed computing. In my talk, I will explain the different areas of my research and their importance as components that make up a blockchain system. For each of these areas, I will also list some of the open questions that I plan to work on in the near future.

Bio: Julian Loss obtained his MSc in computer science from ETH Zurich in 2016 and his Ph.D. from the Ruhr University of Bochum in 2019. He is currently a postdoc at the University of Maryland in the group of Jonathan Katz. His interests include classic cryptographic primitives such as digital signatures and multi-party computation as well as blockchain/consensus protocols.

► VIDEO | Zero-Knowledge for Everything and Everyone

VIDEO | February 5, 2021, 12 pm EDT

Presented by, David Heath
Ph.D. Researcher, Georgia Tech


Zero-Knowledge (ZK) Proofs are important cryptographic objects that allow an untrusted prover to demonstrate to an untrusted verifier the truth of some statement while revealing nothing additional. ZK can potentially be used for complex applications, such as allowing a company to securely conduct an external audit of its records or allowing a code bounty hunter to prove the existence of a software bug without directly showing the vulnerability. Unfortunately, complex ZK applications are difficult to build in practice; existing ZK protocols require statements to be encoded as circuits, and it is difficult to express complex statements as simple circuits. To bring complex ZK applications to practice, developers need a more expressive design language. 

Rather than providing a new design language, we provide an infrastructure that allows existing languages to run in ZK. In this talk, David will present a ‘ZK machine’, a low-level simulated processor that executes arbitrary assembly code in ZK. David will describe the machine, focusing on the inherent challenges and our corresponding solutions. We will explain how we can take off-the-shelf ANSI C programs, compile them to our custom assembly language, and efficiently run this assembly in a ZK protocol. Our system is practical and efficient; for example, it can prove the existence of a CVE-reported bug in gzip in 6.3 seconds. 

The talk will be suitable even for those without cryptographic background. This research was done in collaboration with David’s advisor, Professor Vlad Kolesnikov, as well as Professor David Devecsery and his student Yibin Yang.

Speaker Bio

David Heath is a fifth-year Ph.D. student in Cryptography at Georgia Tech. His research focuses on Secure Multiparty Computation (MPC), a subfield of cryptography that allows users to securely compute over their private data. David’s research improves MPC both by increasing protocol performance and by constructing tools that make MPC more accessible. David is interested in providing end-to-end toolchains for developers that enable users to access cutting-edge cryptographic techniques without needing expertise in the field. David studies under Vlad Kolesnikov, Associate Professor of Cryptography at Georgia Tech.

► VIDEO | Discovering Ad-driven Social Engineering Campaigns at Scale

VIDEO | January 29, 2021, 12 pm EDT

Presented by Phani Vadrevu
Assistant Professor, University of New Orleans


Malicious ads often use social engineering (SE) tactics to coax users into downloading unwanted software, purchasing fake products or services, or giving up valuable personal information. These ads are often served by low-tier ad networks that may not have the technical means (or simply the will) to patrol the ad content they serve to curtail abuse. This lecture will describe a system for large-scale automatic discovery and tracking of SE Attack Campaigns delivered via Malicious Advertisements (SEACMA). The system aims to be generic, allowing us to study the SEACMA ad distribution problem without being biased towards specific categories of ad-publishing websites or SE attacks. Professor Vadrevu will share thoughts on methods to find potential research ideas to focus on in the area of social engineering and web security drawing from personal experiences.

Speaker Bio

Phani Vadrevu is an Assistant Professor in the Department of Computer Science at the University of New Orleans. He is a member of the UNO Cyber Center, a group of faculty members, full-time researchers, and students focused on solving cybersecurity problems. He is interested in all areas of applied security. His current research interests lie in web security topics like phishing, social engineering attacks, and telephony scams. The work often involves applications of machine learning techniques to solve security problems.

Grid Cybersecurity Strategy in an Attacker-Defender Model

January 22, 2021, 12 pm EDT | Virtual Talk LINK

Presented by, Yu-Cheng Chen
Ph.D. student at Georgia Institute of Technology in the School of Electrical and Computer Engineering


With enough computing power and time, an attacker can figure out a password or secret key. This talk addresses modeling the behavior of the attacker and the defender in order to analyze the evolution of cyber-attacks. Chen will introduce an approach that can help cyber-security managers optimize their defense strategies. The analysis provides mathematical proofs and insight into when access controls (such as passwords, internet protocol addresses, and session keys) should be reset to minimize the probability of a successful attack. 

Speaker Bio

Yu-Cheng Chen is a 5th year Ph.D. student at Georgia Institute of Technology in the School of Electrical and Computer Engineering. He graduated from the University of Washington with a double Bachelor’s Degree in Electrical Engineering and Computer Engineering. He also graduated from the University of California, Los Angeles with a Master’s Degree in Electrical Engineering. His research interest is risk assessment in cyber-physical systems.

Securing Democracy in the Fourth Industrial Revolution

January 15, 2021, 12 pm EDT | Virtual Talk LINK

Presented by, L. Jason Anastasopoulos
Assistant Professor in Public Administration and Policy and Political Science at the University of Georgia

In this talk I will be discussing some of my research which focuses on designing systems needed to secure democracy and democratic political institutions, such as elections, in the interconnected digital world of the “fourth industrial revolution.” 

Speaker Bio
Jason is an upcoming fellow at the Safra Center for Ethics at Harvard University and an Assistant Professor at the School of Public and International Affairs, the Department of Statistics (by courtesy) and the Institute for Artificial Intelligence at the University of Georgia. was also recently selected to serve as the Microsoft Visiting Professor of Information Technology Policy at Princeton University.

His research uses behavioral and institutional approaches to understand the threats that emerging technologies pose to democratic institutions, international security and international political economy. He also does research on political methodology focusing on text analysis, image analysis, machine learning and causal inference.

His work has been published or accepted for publication in economics, political science, computer science and public policy journals including the Journal of Human Capital, the American Political Science Review, Political Analysis, the Journal of Public Administration Research and Theory, Proceedings of the Association for the Advancement of Artificial Intelligence, Electoral Studies and others.


► VIDEO | Dec. 2, 2020 | The election may be over, but its shadow still remains. For the last year election security has been a leading concern for governments and constituents. PIT practitioners have been right in the thick of it, working to stanch disinformation, protect voting infrastructure, and make the path to the polls easier.

Our speakers will discuss the role of PIT in election security – what we’ve learned during this election cycle, and how we can use the information in the future.

Moderator: Maurice Turner, Election Security

Expert Speakers: Bruce Schneier, Fellow & Adjunct Lecturer in Public Policy, Harvard’s Kennedy School of Government Richard DeMillo, Chair, School of Cybersecurity and Privacy, Charlotte B. and Roger C. Warren Professor of Computing, Georgia Tech;

Jake Braun, Executive Director Cyber Policy Initiative, Harris School of Public Policy, University of Chicago;

Robin Carnahan, Fellow, Beeck Center for Social Impact and Innovation, Georgetown University

► VIDEO | GT Computing Fireside Chat: Rich DeMillo hosts Kabir Barday

VIDEO | Nov. 19, 2020 |

As part of a new entrepreneurship initiative, the College of Computing is hosting a monthly virtual speaker series with various alumni and faculty around different topics. Rich DeMillo, chair of the School of Cybersecurity and Privacy, will host a fireside chat on entrepreneurship and cybersecurity with Kabir Barday, CS 09, founder and CEO of OneTrust on Nov. 19, 7 p.m. EDT. The talks are open for GT Computing students and alumni to participate, and start with a fireside chat followed by audience Q&A.