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Rei Mizushima

Rei Mizushima

Security Researcher?

Developer by title, security researcher and open-source enthusiast.

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Profile

Where I studied, what I enjoy, and the CTFs I have played.

Education

  1. Middle School

    共愛学園中学校

  2. High School

    共愛学園高等学校

    英語科特進コース

  3. Universitynow

    {REDACTED}

Interests

  • Offensive Security Research
  • Competitive Programming
  • Rhythm Game
  • meow

CTF Participation

  • SECCON 2019 Online CTF
  • 0CTF/TCTF 2022
  • CakeCTF 2023
  • WaniCTF 2023
  • 防衛省サイバーコンテスト 2023
  • Google CTF 2023
  • osu!gaming CTF 2024
  • etc...

Skills

A rough self-assessment, five blossoms being the most comfortable.

  • Frontend
  • Backend
  • Security
  • Rust
  • cat

Language Proficiency

Japanese

Native

English

EIKEN Grade Pre-1 (CEFR B2)

Korean

Good reading & writing, needs improvement in listening & pronunciation

Projects

Open-source work, mostly around social platforms and AI. I care about better user experiences and giving back to the community.

Focus

The areas I spend most of my time on.

Security Research

Offensive security research and vulnerability analysis

CTF Competitions

Active participation in cybersecurity competitions

Open Source Projects

Misskey Tempura and Misskey bot development

Programming Skills

Competitive programming and algorithm development

Certifications

Grouped by field. Security first, then cloud, infrastructure and the rest.

27certifications across 10 fields

セキュリティ

6
  • 登録情報処理安全確保支援士（RISS／登録セキスペ）（更新済み）
  • OSEE (Offensive Security Exploit Expert)
  • CCNP Security
  • CompTIA Security+
  • CompTIA CySA+ (Cybersecurity Analyst)
  • CompTIA PenTest+

Offensive Security

3
  • OSCP (Offensive Security Certified Professional)
  • eWPT (Web Application Penetration Tester)
  • OSED (Offensive Security Exploit Developer)

AWS

4
  • AWS Certified AI Practitioner (AIP-C01)
  • AWS Certified Solutions Architect - Associate (SAA-C03)
  • AWS Certified Security - Specialty (SCS-C02)
  • AWS Certified Developer - Associate (DVA-C02)

Google Cloud

3
  • Cloud Digital Leader
  • Professional Data Engineer
  • Professional Cloud Security Engineer

Cloud/Infrastructure

2
  • Certified Kubernetes Administrator (CKA)
  • HashiCorp Certified: Terraform Associate

Linux

2
  • LPIC-1
  • LPIC-2

IPA 共通

2
  • ITパスポート
  • 基本情報技術者（FE）

IPA 高度

3
  • 応用情報技術者（AP）
  • ネットワークスペシャリスト（NW）
  • データベーススペシャリスト（DB）

AI

1
  • G検定

etc

1
  • 日商簿記3級

Latest writing

All posts

Notes on security research, development and CTFs. Just some random thoughts.

zeta運営はトーク内容を覗けるどころではなかったかもしれない

はじめに：公式の声明 AIチャットアプリ「zeta」の日本公式アカウントが、X（旧Twitter）で以下のような声明を出しました。 「現在、一部の他社広告において、zeta 内の会話内容が運営関係者によって閲覧されているかのような内容が確認されておりますが、そのような事実は一切ございません。」 （引...

4 min readRead