Ashrujit Ghoshal

I am a fifth year PhD student in the Cryptography group of Paul G. Allen School of Computer Science and Engineering at the University of Washington, Seattle, USA. I am advised by Stefano Tessaro and Rachel Lin. I spent the summers of 2021 and 2022 as a research intern at NTT Research Sunnyvale working with Ilan Komargodski. My current research interests lie mainly in the theory and foundations of cryptography.

Prior to this 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

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

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

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

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

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

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

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

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


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