sean9892
I’m Yubin Choi(최유빈), and an undergraduate student at KAIST.
Currently I’m serving in ROK Air Force (2024.02.13-2025.11.12).
Education
- KAIST
- B.S. in School of Computing (2022-Current)
- Chungbuk Science High School
- an year early graduated (2020-2021)
Competitions and Awards
- Security Competitions (CTFs)
- Whitehat Contest 2024 Soldier’s Division 1st place - Team 키보드워리어플랫폼
- 2024 공군 정보통신경연대회 2nd place
- 2024 국방사이버보안경진대회 3rd place - Team 공CERT군
- 2024 공군사이버전사경연대회 3rd place
- Whitehat Contest 2024 General Division 4th place - Team KAIST GoN
- 2022 Crypto Analysis Contest 1st place - Team KAIST GoN
- HackTheon Sejong 2022 4th place - Team KaisTheon
Portfolio
- Published Crypto Challenges to Dreamhack (2021-Current)
- Elliptic Power of CRC: Revenge Challenge of
Power of CRC
; zeroing out CRC value over hidden finite field without solving discrete logarithm
- Elliptic Power of CRC: Revenge Challenge of
- Challenge Author for KAIST GoN Qual (2023-Current)
- Verhältnis: Solving HNP-2H to recover two small integers from their 2-hole masked ratio over the given finite field
- Hoshimachi: LFSR output prediction without solving for full states
- Double Linear: seed recovery on LFSR which adopts AES with a linear s-box as a filter function
- Is it CRT-RSA?: Factoring two RSA moduli with general solution for linear diophantine equation
- Challenge Author for HSPACE Belluminar CTF (2024)
- BabyHash: topological sort to combine inversed hash values with rainbow-table attack on small plaintext space
- Student Instructor at KAIST (2022-2023)
- Humanity/Leadership III <Hacking School>
Extracurricular activities
- Member of Cryptology Wargame Website CryptoHack (2020-Current)
- Solved 233/233 regular challenges, 41st 100%-cleared