Karuppiah Sabari Kumar

Welcome

I'm 0xsabre, a Penetration Tester who spends most days breaking web applications, APIs, and testing security boundaries to find vulnerabilities that matter.

I focus on manual testing, logic flaws, and understanding how systems behave — not just running scanners. I've done vulnerability research and responsible disclosure, with a few CVEs along the way.

This site is where I document my research, share testing methodologies, and write about security concepts I'm exploring. If you're learning security, testing applications, or just curious about how things break — you might find something useful here.