Talks

Payload Compromised: Full Key Recovery in Rocket.Chat E2EE

Hayato Kimura, Ryoma Ito, Kazuhiko Minematsu, and Takanori Isobe

Black Hat Asia 2026 Briefings

Apr 23, 2026

Speaker: Hayato Kimura

Not Sealed: Practical Attacks on Nostr, a Decentralized Censorship-Resistant Protocol

Hayato Kimura, Ryoma Ito, Kazuhiko Minematsu, Shogo Shiraki, and Takanori Isobe

Black Hat USA 2025 Briefings

Aug 6, 2025

Speaker: Hayato Kimura

Acceptance rate: 8.2% (93/1,143).

Key Committing Security of AEZ

Yu Long Chen, Antonio Flórez-Gutiérrez, Akiko Inoue, Ryoma Ito, Tetsu Iwata, Kazuhiko Minematsu, Nicky Mouha, Yusuke Naito, Ferdinand Sibleyras, and Yosuke Todo

The Third NIST Workshop on Block Cipher Modes of Operation 2023

Oct 4, 2023

Speaker: Yu Long Chen