Security engineer / OSCE3 · OSEE / HTB Omniscient
Build from an
attacker’s mindset.
I’m Yunolay, a security engineer working in vulnerability assessment, penetration testing and exploit development. This site collects the tools I build from an attacker’s point of view, along with a log of what I’ve been up to. You can also find me on YouTube and X.
ARTICLES
Articles
Write-ups and long-form posts.
- Exam review
OSEE Review — Our Journey Around the World to AWE
My OSEE (EXP-401 / AWE) write-up — what it is, prerequisites, cost and the exam, plus how two best friends and I traveled the world to train for it.
View details
LOG
Recent activity
Newest first.
- Build
I built a Windows app, “PasteDrawer”
A clipboard history tool you pull out from the screen edge and paste from by drag and drop. The product site is now up.
View details - Build
Released the game “Security Pachi-Slot”
Released a Juggler-style browser slot parodying “security pachinko,” the meme for AI-driven vulnerability research.
- Build
Released the game “Cheat Shogi”
Released a shogi game where cheat cards bend the rules — play the CPU or a friend online with a room ID.
View details - Build
Published the msfvenom one-liner generator
Added a browser tool that generates msfvenom commands and listeners from a dropdown.
View details - Build
Published the Web CheatSheet
Added a pentest / CTF command and technique cheatsheet to the site.
View details - Build
Relaunched yunolay.com
Moved the blog to blog.yunolay.com and rebuilt this site as a home for my activity log and works.
View details - Career
Moved to Fore-Z as Executive Officer
Transferred from Executive Officer at Fore-co.ltd to Executive Officer at Fore-Z.
- Talk
Spoke at OffSecLab Meetup in Shibuya
Gave a talk “OSEE受験記 (OSEE exam write-up)” as Yunolay, introducing OSEE and my exam experience.
View details - Cert
OffSec Exploitation Expert (OSEE)
Earned by passing the EXP-401 (Advanced Windows Exploitation) exam — advanced exploit development including the Windows kernel.
View details - Career
Started writing on note
Published my first article — a self-introduction — on May 17, 2026, and have been posting on note since.
WORKS
Works
Yunolay's Blog
My offensive security blog — HTB and VulnLab walkthroughs, Windows internals and more.
blog.yunolay.com ↗ VideoYouTube channel
Streams and videos as a VTuber.
youtube.com ↗ ToolPasteDrawer
A clipboard history tool for Windows. Pull your history out from the screen edge and drag a clip to paste it. Panel, sticky-note and window views. Currently under review — sales open once the review is complete.
pastedrawer.com ↗ ToolWeb CheatSheet
A pentest / CTF cheatsheet of commands and techniques, from enumeration to web attacks, shells and privilege escalation.
yunolay.com ↗ Toolmsfvenom one-liner generator
A browser tool that builds msfvenom commands and matching multi/handler listeners from a dropdown.
yunolay.com GameCheat Shogi
A shogi variant where you pick one of three cheat cards each turn to bend the rules. Play the CPU, or a friend online with a room ID.
yunolay.com ↗ GameSecurity Pachi-Slot
A Juggler-style browser slot parodying “security pachinko.” Line up 777 for the SQL Injection bonus.
yunolay.com CodeGitHub
Tools and code I have published.
github.com ↗BLOG
Latest blog posts
The blog lives at blog.yunolay.com.
Get in touch
Want to reach me? Head to the contact page.