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SeungHyun Kim

sqrtrev@gmail.com vuln.live sqrtrev @sqrtrev

Skills

Programming Languages C/C++, C#, Python, PHP, SQL, Java, Javascript, x86/x64 Assembly, Bash, Golang Frameworks and tools Burp Suite, GDB, IDA Pro, Binary Ninja, MySQL, SQLite3, MongoDB, Flask, django, apache2, nginx, node.js The things that I can do Backend Web Development, Socket Programming, Reverse engineering/exploit development for x86, Windows API based Programming, Pentest, Solidity

Education

Korea University Republic of Korea

BACHELOR DEGREE March, 2019 ‑ August, 2023

  • GPA 3.48 / 4.5

Korea University Republic of Korea

MASTER DEGREE September, 2023 - August, 2025

  • GPA 3.50 / 4.5

Experience

Korea University Republic of Korea

UNDERGRADUATE RESEARCHER August, 2020 ‑ January, 2021

  • Bug hunting from a computer hardware community which is named ”QuasarZone” and has over 200,000 users
  • Reported 0‑day vulnerability on Wordpress plugin and got assigned CVE‑2020‑23325

Pentest at N***** Republic of Korea

RED Team June, 2021 - Jan, 2022

  • Worked with CYDF and School of Cybersecurity of Korea University
  • Found some critical vulnerabilities

HAECHI LABS Republic of Korea

Security Researcher April, 2022 - August, 2023

  • Blockchain & Web Security

Zellic USA (remote)

Security Researcher August, 2023 -

  • Blockchain & Web Security

Activity

Conference Speaker Republic of Korea

  • The Hacker Owl 2th - Topic: PHP output buffering analysis in php-src level

CTF Player (a.k.a hacking competition) International

  • Founded a team named ”Super Guesser” which was ranked 3rd place globally in 2021
  • Play CTFs with team Super Guesser and WreckTheLine

CTF Challenge Author International

  • A web challenge (about abusing PHP execution timeline with Segmentation Fault and session.upload_progress.cleanup) at IJCTF 2021
  • Three web challenges (about Prototype Pollution + SQL Quine, DNS rebinding, pwn PHP via Zend module) at ASIS CTF 2020
  • Three challenges (about DOM Clobbering, blind regular expression injection, pwn custom C++ http server) at IJCTF CTF 2020
  • A web challenge (about XSS using SQL Injection with OUTFILE for bypassing CSP) at Belluminar 2019
  • Lead challenge author of WACON (2022 ~)
  • A part of ACSC CTF Organizers

0‑day research

  • SQL Injection at Wordpress Plugin / CVE‑2020‑23325
  • Reported 0‑day vulnerability of Windows explorer.exe to MSRC(Microsoft Security Response Center / VULN‑044164)
  • Apple SMTH / waiting for being patched

Security Blog

  • I write about CTF write ups normally. - currently under maintenance

Honors & Awards

2025 2nd place, SECCON CTF 13 Final International
3rd place, DEFCON CTF 33 Final (Team SuperDiceCode) International
4th place, BlackHat Mea CTF (Team Guper Suesser) International
2024 3rd place, DEFCON CTF 32 Final (Team SuperDiceCode) International
2023 Finalist, SECCON CTF 2023 International
Finalist, HITCON CTF 2023 International
4th place, DEFCON CTF 31 Prequal International
3rd place, LINE CTF 2023 International
2nd place, Samsung SSTF 2023 International
2nd place, Whitehat Contest 2023 (Prize: 10,000,000 KRW) Republic of Korea
2022 1st place, WhiteHat Contest 2022 (Prize: 20,000,000 KRW) Republic of Korea
2nd place, BlackHat Mea CTF (Team {{7*7}}, Prize: 200,000 SAR) International
Finalist, DEFCON CTF 30 Final International
1st place, LINE CTF 2022 (Prize: $5,000 USD) International
3rd place, Codegate 2022 (University Section) Republic of Korea
3rd place, CCE 2022 (General Section 3rd place prize) Republic of Korea
2021 1st place, SECCON CTF 2021 (Prize: 400,000 JPY) International
2nd place, CCE 2021 Prequal (General Section) Republic of Korea
2nd place, International Cybersecurity Challenge (Team Asia) International
2nd place, Whitehat Contest 2021 (General Section, Prize: 10,000 USD) Republic of Korea
3rd place, Samsung CTF 2021 (SSTF, Prize: Samsung Electronics (almost 1,000 USD)) International
Qualified for Final, XCTF Final International
Qualified for Final, Google CTF 2021 International
3rd place, LINE CTF (Prize: 2,000 USD) International
6th place, DEFCON CTF 29 Final International
2020 1st place, HITCON CTF (Prize: 8,192 USD, DEFCON 29 Final Ticket) International
1st place, Dragon CTF (Prize: 2,000 USD) International
Finalist, Cyber Operations Competition (General Seciton) Republic of Korea
Finalist, Codegate 2020 (University Section, USACykor) Republic of Korea
3rd place, hxpCTF 2020 International
2016 Finalist, Codegate 2016 (Junior Section) International
2015 4th place, WhiteHat Contest 2015 (Junior Section, Final) Republic of Korea
Finalist, Codegate 2015 (Junior Section) International
Prize by Hauri, YISF 2015 Republic of Korea
2014 Finalist, Seucrity Olympiad Republic of Korea
Prize by Ahnlab, YISF 2014 Republic of Korea