Paul Grubbs's Academic Website

About Me

I am an Assistant Professor in EECS at the University of Michigan. My email address is paulgrub AT umich DOT edu.
If you're interested in working with me, read this before sending an email. I am currently recruiting graduate students.
I use he/him/his pronouns.

Research

My research is in applied cryptography, security, and systems. In my work, I use a wide array of theoretical and practical tools to both prevent security failures (e.g., identifying flaws in existing cryptographic primitives, and building new ones) and reduce the harm failures can cause (e.g., designing new key-value stores that protect data even if they are compromised).

My research interests are broad, but a recurring interest is the interface between cryptographic primitives or protocols and the systems that use them: surprising and subtle things often happen here.

Some of my other interests are censorship, privacy, legal and ethical issues related to information security, and the intersection of technology and society.

Publications (* = authors contributed equally)
See also: Google Scholar, DBLP

Zero-Knowledge Middleboxes (in submission)
Paul Grubbs, Arasu Arun, Ye Zhang, Joseph Bonneau, Michael Walfish
Arasu spoke about this paper at the sdns://2021 workshop. Watch his talk here.

Anonymous, Robust Post-Quantum Public Key Encryption (in submission)
Paul Grubbs, Varun Maram, Kenneth G. Paterson
Varun presented some of our results at NIST's Third PQC Standardization Conference.

Partitioning Oracle Attacks USENIX Security 2021
Julia Len, Paul Grubbs, Thomas Ristenpart

Pancake: Frequency Smoothing for Encrypted Data Stores USENIX Security 2020 (Distinguished Paper Award)
Paul Grubbs*, Anurag Khandelwal*, Marie-Sarah Lacharité*, Lloyd Brown, Lucy Li, Rachit Agrawal, and Thomas Ristenpart

Asymmetric Message Franking: Content Moderation for Metadata-Private End-to-End Encryption CRYPTO 2019
Nirvan Tyagi, Paul Grubbs, Julia Len, Ian Miers, and Thomas Ristenpart

Learning to Reconstruct: Statistical Learning Theory and Encrypted Database Attacks IEEE Symposium on Security and Privacy 2019
Paul Grubbs, Marie-Sarah Lacharité, Brice Minaud, and Kenneth G. Paterson
Blogs about this work: Matt Green, Bruce Schneier

Pump Up The Volume: Practical Database Reconstruction from Volume Leakage on Range Queries CCS 2018
Paul Grubbs, Marie-Sarah Lacharité, Brice Minaud, and Kenneth G. Paterson

Fast Message Franking: From Invisible Salamanders to Encryptment CRYPTO 2018
Yevgeniy Dodis, Paul Grubbs, Thomas Ristenpart, and Joanne Woodage
Here's a video of Joanne's RWC 2019 talk on this work.

The Tao of Inference in Privacy-Protected Databases PVLDB 2018
Vincent Bindschaedler, Paul Grubbs, David Cash, Thomas Ristenpart, and Vitaly Shmatikov

Message Franking via Committing Authenticated Encryption CRYPTO 2017
Paul Grubbs, Jiahui Lu, and Thomas Ristenpart
Zoom's current end-to-end encryption design (v2) uses the CtE1 scheme we introduced in this work.

Why Your Encrypted Database Is Not Secure HotOS 2017 (slides)
Paul Grubbs, Thomas Ristenpart, and Vitaly Shmatikov

Leakage-Abuse Attacks against Order-Revealing Encryption IEEE Symposium on Security and Privacy 2017
Paul Grubbs, Kevin Sekniqi, Vincent Bindschaedler, Muhammad Naveed, and Thomas Ristenpart

Side-Channel Attacks on Shared Search Indexes IEEE Symposium on Security and Privacy 2017
Liang Wang, Paul Grubbs, Jiahui Lu, Vincent Bindschaedler, David Cash, and Thomas Ristenpart

Modifying an Enciphering Scheme After Deployment Eurocrypt 2017
Paul Grubbs, Thomas Ristenpart, and Yuval Yarom

Breaking web applications built on top of encrypted data CCS 2016
Paul Grubbs, Richard McPherson, Muhammad Naveed, Thomas Ristenpart, and Vitaly Shmatikov
FAQ about this work

Leakage-Abuse Attacks Against Searchable Encryption CCS 2015
David Cash, Paul Grubbs, Jason Perry, and Thomas Ristenpart

GPU and CPU parallelization of honest-but-curious secure two-party computation ACSAC 2013
Nathaniel Husted, Steve Myers, abhi shelat, and Paul Grubbs

My Dissertation

Breaking and Building Encrypted Databases (filed August 2020)
I was very humbled to receive a Cornell CS Dissertation Award for this work.

Talks

Pancake: Frequency Smoothing for Encrypted Data Stores Real World Cryptography 2021
Hunting Invisible Salamanders: Cryptographic (in)Security with Attacker-Controlled Keys BlackHat, August 2020
   An article and video about my talk appeared on Dark Reading.
Learning to Reconstruct: Statistical Learning Theory and Encrypted Database Attacks ICERM Workshop on Encrypted Search, June 2019
Message Franking: Invisible Salamanders, Encryptment, and AMFs
   NYC Crypto Day (May 2019), Workshop on Secure Messaging (May 2019), Stanford Security Seminar (May 2019)
Why Your Encrypted Database is Not Secure Second ESSA workshop, 2018
Breaking web applications built on top of encrypted data Real World Cryptography 2017
New Inference Attacks on Order-Preserving Encryption DC Crypto Day, May 2016
On Deploying Property-Preserving Encryption Real World Cryptography 2016
Searchable Encryption...in the REAL world ESSA Workshop, 2015

Teaching

Winter 2022: EECS 598/498 (Research seminar, name TBD)
Fall 2021: EECS 575 (Advanced Cryptography)

During grad school, I was a teaching assistant for CS 5830 (Cryptography) in Spring 2017 and CS 5435 (Security and Privacy Concepts in the Wild) in Fall 2019.

Service

I was (or am) a program committee member for: SAC 2019, CT-RSA 2021, PETS 2021, CRYPTO 2021, IEEE S&P 2022, PETS 2022
I was honored to serve as a mentor for the 2020 Rising Stars workshop.

Bio

For the 2020-2021 academic year, I was a postdoc at NYU, working with Michael Walfish and Joseph Bonneau as a part of the Pepper project.

I did my PhD in Computer Science department at Cornell University, advised by the inimitable Tom Ristenpart. I spent my first year in gorgeous Ithaca, and the rest of the time at the Cornell Tech campus in NYC. In Spring 2018, I was hosted by Kenny Paterson in a visit to Royal Holloway, University of London, located in scenic Egham, UK. My graduate studies were supported in part by a 2017 NSF Graduate Research Fellowship (GRF). My GRF materials are available on request.

Between undergrad and grad school, I worked for two and a half years at Skyhigh Networks (now McAfee) as a cryptography engineer.

I did my undergrad at Indiana University, where I majored in Math and Computer Science.

Miscellaneous

You can tweet at me @pag_crypto or find me on LinkedIn.

When I'm not working, I enjoy watching mysteries and comedies, reading, listening to (and occasionally playing) music, and spending time outside in my hammock.
Me recently
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