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<span style="font-family: Arial; font-weight: 700;"><i>Department of Computer Science Seminar</i></span></div>
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<span style="font-family: Arial; font-size: 11pt; color: rgb(0, 0, 0); font-weight: 700;">Amir Herzberg<br>
Comcast Professor for Cybersecurity Innovation </span></p>
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<span style="font-family: Arial; font-size: 11pt; color: rgb(0, 0, 0); font-weight: 700;">University of Connecticut</span></p>
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<span style="font-family: Arial; font-size: 11pt; color: rgb(0, 0, 0); font-weight: 700;">Wednesday, March 6th<br>
11:00am - 12:00pm<br>
In Person: John Crerar Library 390</span></p>
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<span style="font-family: Arial; font-size: 11pt; color: rgb(0, 0, 0); background-color: rgb(255, 255, 255); font-weight: 700;">Talk Title:
</span><span style="font-family: Arial; font-size: 11pt; color: rgb(36, 36, 36); background-color: rgb(255, 255, 255); font-weight: 700;">Provable Security for PKI Schemes and the Composable Modular Security Specifications Framework</span></p>
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<span style="font-family: Arial; font-size: 11pt; color: rgb(0, 0, 0); background-color: rgb(255, 255, 255); font-weight: 700;">Abstract</span><span style="font-family: ArialMT; font-size: 11pt; color: rgb(0, 0, 0); background-color: rgb(255, 255, 255);">:
</span><span style="font-family: ArialMT; font-size: 11pt; color: rgb(36, 36, 36); background-color: rgb(255, 255, 255);">PKI schemes provide a critical foundation for applied cryptographic protocols. However, there are no rigorous security specifications for
realistic PKI schemes, and therefore, no PKI schemes were proven secure. Cryptographic systems that use PKI are analyzed by adopting overly simplified models of the PKI, often, simply assuming secure public keys. This is problematic considering the extensive
reliance on PKI, the multiple failures of PKI systems, and the fact that proposed and deployed PKI are complex, have complex requirements and assume complex models.</span></p>
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<span style="font-family: ArialMT; font-size: 11pt; color: rgb(36, 36, 36); background-color: rgb(255, 255, 255);">We present game-based security specifications for PKI schemes, and analyse important, widely deployed PKIs: PKIX and two variants of Certificate
Transparency (CT). All PKIs are based on the X.509v3 standard and its CRL revocation mechanism. Our analysis identified few subtle vulnerabilities, and includes reduction-based proofs showing that the PKIs ensure specific requirements under specific models
(assumptions). To our knowledge, this is the first reduction-based definition and proof of security for a realistic PKI scheme.</span></p>
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<span style="font-family: ArialMT; font-size: 11pt; color: rgb(36, 36, 36); background-color: rgb(255, 255, 255);">Our specifications and analysis use the Modular Security Specifications (MoSS) framework [Crypto'21]. The talk will explain the relevant aspects
of MoSS. We may briefly discuss the extensions that allow provably-secure compositions of protocols.</span></p>
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<span style="font-family: Arial; font-size: 11pt; color: rgb(0, 0, 0); background-color: rgb(255, 255, 255); font-weight: 700;">Bio</span><span style="font-family: ArialMT; font-size: 11pt; color: rgb(0, 0, 0); background-color: rgb(255, 255, 255);">:
</span><span style="font-family: ArialMT; font-size: 11pt; color: rgb(36, 36, 36); background-color: rgb(255, 255, 255);">Dr. Herzberg's is the Comcast professor for Cybersecurity Innovation in the school of computing of the University of Connecticut. His research
areas include internet security, applied cryptography, privacy and anonymity, usable security, security for cyber-physical systems, and social, economic and legal aspects of security. Dr. Herzberg earned his Ph.D. in Computer Science in 1991 from the Technion
in Israel. From 1991 to 1995, he worked at the IBM T.J. Watson Research Center, where he was a research staff member and the manager of the Network Security research group. From 1996 to 2000, Dr. Herzberg was the Manager of E-Business and Security Technologies
at the IBM Haifa Research Lab. From 2002 to 2017, he was a professor in Bar Ilan University (Israel). Since 2017, he is professor at University of Connecticut.</span></p>
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<b>Abigail Santana</b></div>
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Business Assistant - Computer Science</div>
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The University of Chicago</div>
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5730 S Ellis Ave, JCL 212</div>
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Chicago, IL 60637</div>
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<span style="color: rgb(12, 100, 192);"><u>asantana01@uchicago.edu</u></span></div>
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Office: 773-834-2750</div>
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