Rubén Santos García
I build tools, break things in labs, and write down what I learn.
Get in Touch👋 About Me
I work in offensive security. Most of my time goes to pentesting, Active Directory and web and API targets, and to writing small tools that make that work faster.
Kayssel is where I keep my notes in public. When I learn a technique properly, from a lab or from real work, I turn it into a chapter of a series so I can find it again and so you can follow the same path.
Everything here is written with the help of AI and then run, tested and reviewed by me. The details are on the About page.
🛠️ Expertise & Focus Areas
Penetration Testing
Red teaming, vulnerability assessment, and exploitation techniques
Active Directory
Domain exploitation, privilege escalation, and lateral movement
Web & API Security
OWASP Top 10, API exploitation, and web application pentesting
Web3 Security
Smart contract auditing, blockchain security, and DeFi analysis
Mobile Security
Android/iOS pentesting, app reverse engineering, and exploit development
Binary Analysis
Reverse engineering, malware analysis, and exploitation
Tool Development
Python automation, offensive security tooling, and scripting
Writing
Turning labs and engagements into series you can follow in order
✉️ Get in touch
Questions about a post, a mistake you spotted, or a topic you would like covered? Email is the fastest way. I read everything, even when I answer slowly.