I am a Postdoctoral Fellow at Carnegie Mellon University advised by Elaine Shi. I received my PhD in Computer Science from the University of Washington, advised by Stefano Tessaro and Rachel Lin. I spent the summers of 2021 and 2022 as a research intern at NTT Research working with Ilan Komargodski. My current research interests lie mainly in the theory and foundations of cryptography.

Even earlier, I graduated from the Indian Institute of Technology, Kharagpur in July 2018 with a Bachelor of Technology (Hons.) in Computer Science and Engineering. I was advised by Debdeep Mukhopadhyay for my undergraduate thesis.

Publications and Manuscripts

Offline-Online Indifferentiability of Cryptographic Systems [eprint]
Ashrujit Ghoshal, Ilan Komargodski, Gil Segev
Preprint

Information-Theoretic Multi-Server PIR with Global Preprocessing [eprint]
Ashrujit Ghoshal, Baitian Li, Yaohua Ma, Chenxin Dai, Elaine Shi
Preprint

Pseudorandom Functions with Weak Programming Privacy and Applications to Private Information Retrieval
Ashrujit Ghoshal, Mingxun Zhou, Elaine Shi, Bo Peng
EUROCRYPT 2025

Efficient Pre-processing PIR Without Public-Key Cryptography [eprint] [doi]
Ashrujit Ghoshal, Mingxun Zhou, Elaine Shi
EUROCRYPT 2024

The Query-Complexity of Preprocessing Attacks [eprint] [doi] [talk] [slides]
Ashrujit Ghoshal, Stefano Tessaro
CRYPTO 2023

Optimal Security for Keyed Hash Functions: Avoiding Time-Space Tradeoffs for Finding Collisions [eprint] [doi] [slides]
Cody Freitag, Ashrujit Ghoshal, Ilan Komargodski
EUROCRYPT 2023

Time-Space Tradeoffs for Sponge Hashing: Attacks and Limitations for Short Collisions [eprint] [doi] [talk] [slides]
Cody Freitag, Ashrujit Ghoshal, Ilan Komargodski
CRYPTO 2022

On Time-Space Tradeoffs for Bounded-Length Collisions in Merkle-Damgård Hashing [eprint] [doi] [talk] [slides]
Ashrujit Ghoshal, Ilan Komargodski
CRYPTO 2022

Hiding in Plain Sight: Memory-tight Proofs via Randomness Programming [eprint] [doi] [talk] [slides]
Ashrujit Ghoshal, Riddhi Ghosal, Joseph Jaeger, Stefano Tessaro
EUROCRYPT 2022

Tight State-Restoration Soundness in the Algebraic Group Model [eprint] [doi] [talk] [slides]
Ashrujit Ghoshal and Stefano Tessaro
CRYPTO 2021

The Memory-Tightness of Authenticated Encryption [eprint] [doi] [talk] [slides]
Ashrujit Ghoshal, Joseph Jaeger, Stefano Tessaro
CRYPTO 2020

On the Memory-Tightness of Hashed ElGamal [eprint] [doi] [talk] [slides]
Ashrujit Ghoshal and Stefano Tessaro
EUROCRYPT 2020

Lightweight and Side-channel Secure 4 × 4 S-Boxes from Cellular Automata Rules [eprint] [doi]
Ashrujit Ghoshal, Rajat Sadhukhan, Sikhar Patranabis, Nilanjan Datta, Stjepan Picek, Debdeep Mukhopadhyay
IACR Transactions on Symmetric Cryptology, 2018(3) and FSE 2019

Template-Based Fault Injection Analysis of Block Ciphers [eprint] [doi]
Ashrujit Ghoshal, Sikhar Patranabis, Debdeep Mukhopadhyay
SPACE 2018

Several Masked Implementations of the Boyar-Peralta AES S-Box [eprint] [doi]
Ashrujit Ghoshal and Thomas De Cnudde
INDOCRYPT 2017

An Evaluation of Lightweight Block Ciphers for Resource-Constrained Applications: Area, Performance, and Security [doi]
Rajat Sadhukhan, Sikhar Patranabis, Ashrujit Ghoshal, Debdeep Mukhopadhyay, Vishal Saraswat, Santosh Ghosh
Journal of Hardware and Systems Security 2017

Other

Tradeoffs in Cryptography [UW libraries]
Doctoral Thesis

Implementation Attacks on Block Ciphers: New Approaches and Countermeasures [pdf]
Bachelors Thesis