The paper “Extended Analysis of Key Committing Security of HCTR2” has been accepted at the Selected Areas in Cryptography 2026 conference. This is second-longest running North-American cryptography conference, held in Canada every year since 1994.
This paper presents an analysis of the key committing security of EtE-HCTR2, a robust authenticated encryption scheme constructed from HCTR2 and the Encode-then-Encipher (EtE) framework, in light of the ongoing standardization effort of cryptographic accordions by NIST. The results are both in the classical and the post-quantum setting.
It is co-authored by Donghoon Chang, Yukihito Hiraga, Kazuhiko Minematsu, Nicky Mouha, Yusuke Naito, Yu Sasaki, Rentaro Shiba, Takeshi Sugawara, Kazuhiko Minematsu, Yu Sasaki, and Rentaro Shiba.