ⓗⓔⓛⓛⓞ! (👍≖‿‿≖)👍 👍(≖‿‿≖👍)

Now I am a PhD student under the guidance of Yanbin Pan and I also spent one year in the Crypto Group at Aarhus University, hosted by Diego F. Aranha. My research interests primarily focus on applying Algorithmic Number Theory and Combinatorics to problems in Cryptography. I prefer problems with a strong mathematical structure, such as those with an algebraic or combinatorial flavor.

Together with my collaborators, we introduced additive combinatorics into Coppersmith’s method, which enabled us to remove manual calculations of success conditions. This work was accepted to Crypto’25, and we also have several interesting applications and follow-up results.

Currently, I am interested in leakage-resilient secret sharing, not only in terms of lower bounds but also in proving security. I particularly enjoy the Fourier analysis and additive combinatorics tools used in this area.

🔴 I am currently looking for a postdoc.

Selected Publications

ヾ(＾∇＾) Some of my favourite results (A full list of publications):

• Computing Asymptotic Bounds for Small Roots in Coppersmith’s Method via Sumset Theory. Crypto'25 [PDF][CODE]
  By introducing the Sumsets theory from Additive Combinatorics as a new analytical tool, we develop the first provable algorithm for determining these asymptotic bounds, which significantly streamlines manual calculations.

• Small Public Exponent Brings More: Improved Partial Key Exposure Attacks against RSA. CIC'24 [PDF][CODE]
  We improve the attack by Boneh et al. at Asiacrypt ‘98 and achieve a 2^10 (or 1,024) x improvement in the running time for e = 65,537.

• Embedding Integer Lattices as Ideals into Polynomial Rings. ISSAC'24 [PDF][CODE]
  An algorithm to verify whether a given full-rank lattice in Z^n is an ideal lattice and output all the polynomial rings.

Activities

Trips & Talks

External Reviewer: IEEE TDSC 2025, Africacrypt 2025, Asiacrypt 2025

Miscellaneous

ʕ•̫͡•ʕ•̫͡•ʔ•̫͡•ʔ•̫͡•ʕ•̫͡•ʔ•̫͡•ʔ

• [Useful-Link] A cute website contains many useful links.

Contact

Github | DBLP | Google Scholar | fengyansong [at] amss.ac.cn