Akshima

I am currently a postdoctoral fellow in the CS department at NYU Shanghai, where I am working with Siyao Guo. 

Prior to this, I completed my PhD from University of Chicago in 2022. I was very fortunate to be advised by David Cash at UChicago. Prior to joining UChicago, I was a PhD student at Rutgers University until 2018.

I have completed my B.Tech in CSE from IIIT-Delhi in 2016, where I was advised by Donghoon Chang and Somitra Sanadhya. I mostly worked on Cryptanalysis under their esteemed guidance.

My research interests broadly include cryptography and related areas of security and theoretical computer science. Recently I am fascinated to investigate the role of memory and space in the security of cryptographic primitives. My research is funded by the Ministry of Education of China.

• Time-Space Tradeoffs for Finding Multi-collisions in Merkle Damgård Hash Functions

Akshima

ITC 2024 [link] 

• Tight Time-Space Tradeoffs for the Decisional Diffie-Hellman Problem

Akshima, Tyler Besselman, Siyao Guo, Yuping Ye, Zhiye Xie

STOC 2024 [eprint] 

• Time-Space Lower Bounds for Finding Collisions in Merkle-Damgård Hash Functions

Akshima, Siyao Guo, Qipeng Liu

Journal of Cryptology [link] 

• On Time-Space Lower Bounds for Finding Short Collisions in Sponge Hash Functions

Akshima, Xiaoqi Duan, Siyao Guo, Qipeng Liu

TCC 2023 [eprint]

• Time-Space Lower Bounds for Finding Collisions in Merkle-Damgård Hash Functions

Akshima, Siyao Guo, Qipeng Liu

CRYPTO 2022 [eprint]  (Invited to Journal of Cryptology)

• Time-Space Tradeoffs and Short Collisions in Merkle-Damgård Hash Functions

Akshima, David Cash, Andrew Drucker, Hoeteck Wee

CRYPTO 2020 [eprint]

• Full Database Reconstruction in Two Dimensions

Francesca Falzon, Evangelia Anna Markatou, Akshima, David Cash, Adam Rivkin, Jesse Stern, Roberto Tamassia

CCS 2020 [paper]

• Generation of Secure and Reliable Honeywords, Preventing False Detection

Akshima, Donghoon Chang, Aarushi Goel, Sweta Mishra, Somitra Kumar Sanadhya

IEEE Transactions on on Dependable and Secure Computing 2018 [pdf]

• Single Key Recovery Attacks on 9-Round Kalyna-128/256 and Kalyna-256/512

Akshima, Donghoon Chang, Mohona Ghosh, Aarushi Goel, Somitra Kumar Sanadhya

ICISC 2015 [eprint]

• Improved Meet-in-the-Middle Attacks on 7 and 8-Round ARIA-192 and ARIA-256

Akshima, Donghoon Chang, Mohona Ghosh, Aarushi Goel, Somitra Kumar Sanadhya

INDOCRYPT 2015 [pdf]

• Time-Space Trade-offs for Hash Collisions

DSO National Laboratories, Singapore

• Time-Space Trade-offs for Hash Collisions

Indian Institute of Technology (IIT) Bombay

• Time-Space Trade-offs for Hash Collisions

Indian Institute of Sciences (IISc) Bangalore

• Time-Space Trade-offs for Hash Collisions

Indian Institute of  Technology (IIT) Jodhpur

• Time-Space Lower Bounds for Finding Collisions in Merkle-Damgård Hash Functions

CRYPTO 2022

• Time-Space Trade-offs and Short Collisions in Merkle-Damgård Hash Functions

CRYPTO 2020

• Improved Meet-in-the-Middle Attacks on 7 and 8-Round ARIA-192 and ARIA-256

IndoCrypt 2015

• Program Committee: ASIACRYPT 2024, ProTeCS 2025

• External Reviewer: J. CRYPTOL., CRYPTO, EUROCRYPT, STOC, ACM CCS, TCC, ITCS, ASIACRYPT, PKC

• Introduction to Cryptography

Teaching Assistant: Spring 22, Autumn 21, Autumn 20

• Usable Security and Privacy

Teaching Assistant: Spring 21

• Discrete Mathematics

Teaching Assistant: Winter 21

• Algorithms

Teaching Assistant: Spring 20

• Linear Algebra and its Applications

Teaching Assistant: Winter 20

• Discrete Structures

Teaching Assistant: Spring 17

• Algorithms

Teaching Assistant: Fall 16