Hey there, I am Neil Zhao (赵子瑞/趙子瑞), currently a post-doc researcher at NVIDIA Research. Starting in the Fall of 2025, I will be an Assistant Professor in the Department of Electrical and Computer Engineering at the University of Texas at Austin. I received my PhD degree in Computer Science from the University of Illinois Urbana-Champaign (UIUC) in 2024, where I was advised by Prof. Josep Torrellas. Prior to that, I completed my Bachelor of Science in Applied Physics at the University of Science and Technology of China (USTC) in 2018. At USTC, I was part of the School of the Gifted Young and was selected for the Yan Jici Talent Students Program.
My research interests lie in Computer Architecture, System Security, and Cloud Computing. Specifically, I study side-channel attacks and defenses across the full cloud-computing stack in realistic cloud settings. I have recently demonstrated end-to-end side-channel attacks within Google Cloud’s production environment [ASPLOS 2024a, ASPLOS 2024b] and discovered a low-noise side channel in Intel CPUs [USENIX Security 2022]. Moreover, I designed side-channel defenses from a wide range of angles, including information theory [ASPLOS 2023], CPU cache systems [ASPLOS 2022], operating systems [ISCA 2024], program analyses [MICRO 2020, ASPLOS 2021], and data-oblivious programming practices [CCS 2023]. I received W. J. Poppelbaum Memorial Award for creativity in computer architecture design from the CS department of UIUC in 2023. My long-term vision is to build secure and efficient public clouds resistant to side-channel attacks.
Contact Information: I am best reached via email at neilz@utexas.edu.
I am always looking for students who are passionate about hardware/system security, computer architecture, and cloud computing. If you’re interested in working with me, please feel free to send your CV via email.
Publications
Perspective: A Principled Framework for Pliable and Secure Speculation in Operating Systems
by Tae Hoon Kim, David Rudo, Kaiyang Zhao, Zirui Neil Zhao, and Dimitrios Skarlatos
51st International Symposium on Computer Architecture (ISCA 2024), pages 739-755, Buenos Aires, Argentina, June 2024
[paper]Last-Level Cache Side-Channel Attacks Are Feasible in the Modern Public Cloud
by Zirui Neil Zhao, Adam Morrison, Christopher W. Fletcher, Josep Torrellas
29th ACM International Conference on Architectural Support for Programming Languages and Operating Systems (ASPLOS 2024), Volume 2, pages 582-600, La Jolla, CA, USA, May 2024
[paper, slides, code]Everywhere All at Once: Co-Location Attacks on Public Cloud FaaS
by Zirui Neil Zhao, Adam Morrison, Christopher W. Fletcher, Josep Torrellas
29th ACM International Conference on Architectural Support for Programming Languages and Operating Systems (ASPLOS 2024), Volume 1, pages 133-149, La Jolla, CA, USA, May 2024
[paper, slides, code]Declassiflow: A Static Analysis for Modeling Non-Speculative Knowledge to Relax Speculative Execution Security Measures
by Rutvik Choudhary, Alan Wang, Zirui Neil Zhao, Adam Morrison, Christopher W. Fletcher
ACM SIGSAC Conference on Computer and Communications Security (CCS 2023), pages 2053-2067, Copenhagen, Denmark, November 2023
[paper]Untangle: A Principled Framework to Design Low-Leakage, High-Performance Dynamic Partitioning Schemes
by Zirui Neil Zhao, Adam Morrison, Christopher W. Fletcher, Josep Torrellas
28th ACM International Conference on Architectural Support for Programming Languages and Operating Systems (ASPLOS 2023), Volume 3, pages 771-788, Vancouver, BC, Canada, March 2023
[paper, slides]
IEEE Micro Top Picks 2024 Honorable MentionBinoculars: Contention-Based Side-Channel Attacks Exploiting the Page Walker
by Zirui Neil Zhao, Adam Morrison, Christopher W. Fletcher, Josep Torrellas
31st USENIX Security Symposium (USENIX Security 2022), pages 699-716, Boston, MA, USA, August 2022
[paper, slides, code]Pinned Loads: Taming Speculative Loads in Secure Processors
by Zirui Neil Zhao, Houxiang Ji, Adam Morrison, Darko Marinov, Josep Torrellas
27th ACM International Conference on Architectural Support for Programming Languages and Operating Systems (ASPLOS 2022), pages 314–328, Lausanne, Switzerland, March 2022.
[paper, slides, code]PaCon: A Symbolic Analysis Approach for Tactic-Oriented Clustering of Programming Submissions
by Yingjie Fu, Jonathan Osei-Owusu, Angello Astorga, Zirui Neil Zhao, Wei Zhang, Tao Xie
ACM SIGPLAN International Symposium on SPLASH-E, pages 32-42, Chicago, IL, USA, October 2021
[paper]Jamais Vu: Thwarting Microarchitectural Replay Attacks
by Dimitrios Skarlatos*, Zirui Neil Zhao*, Riccardo Paccagnella, Christopher W. Fletcher, Josep Torrellas
26th ACM International Conference on Architectural Support for Programming Languages and Operating Systems (ASPLOS 2021), pages 1061-1076, Virtual Event, April 2021
*Authors contributed equally to this work
[paper, slides, code]Speculative Interference Attacks: Breaking Invisible Speculation Schemes
by Mohammad Behnia, Prateek Sahu, Riccardo Paccagnella, Jiyong Yu, Zirui Neil Zhao, Xiang Zou, Thomas Unterluggauer, Josep Torrellas, Carlos V. Rozas, Adam Morrison, Frank McKeen, Fangfei Liu, Ron Gabor, Christopher W. Fletcher, Abhishek Basak, Alaa R. Alameldeen
26th ACM International Conference on Architectural Support for Programming Languages and Operating Systems (ASPLOS 2021), pages 1046-1060, Virtual Event, April 2021
[paper, slides, code]Speculation Invariance (InvarSpec): Faster Safe Execution Through Program Analysis
by Zirui Neil Zhao, Houxiang Ji, Mengjia Yan, Jiyong Yu, Christopher W. Fletcher, Adam Morrison, Darko Marinov, Josep Torrellas
53rd Annual IEEE/ACM International Symposium on Microarchitecture (MICRO 2020), pages 1138–1152, Virtual Event, October, 2020
[paper, slides]Benchmarking the Capability of Symbolic Execution Tools with Logic Bombs
by Hui Xu, Zirui Neil Zhao, Yangfan Zhou, Michael R. Lyu
IEEE Transactions on Dependable and Secure Computing, volume 17, issue 6, pages 1243–1256, 2020
[paper, code]
Teaching
- Parallel Computer Architecture (UIUC), Spring 2023 — Teaching Assistant
- C Language Programming II (USTC), Spring 2017 — Teaching Assistant
- Electromagnetism B (USTC), Fall 2016 — Teaching Assistant
Service
- Program Committee, Top Picks in Hardware and Embedded Security, 2024
- Program Committee, Symposium on High-Performance Computer Architecture (HPCA), 2024
- Panelist, “Demystifying Grad School” at the Young Architect Workshop, 2024
- Web Chair, 28th International Symposium on Model Checking of Software (SPIN), 2022
- Co-Reviewer, Automated Software Engineering (ASE), 2020 and 2021
- Co-Reviewer, Conference on Computer and Communications Security (CCS), 2019
- Co-Reviewer, International Conference on Software Engineering (ICSE), 2019