// Cyber Security Engineer

Protecting the digital world, one lab at a time.

Pasindu Sandeepa. Junior Researcher specializing in Penetration Testing and Network Defense. Based in Sri Lanka.

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About
Pasindu Sandeepa

A self taught with a lot of interest in Cyber Security

Hi, I am Pasindu, a 2nd year Computer Science undergraduate at Eastern University Sri Lanka, based in Kandy. My interest has always been in Cyber Security. I want to ensure that security is a top priority within our quickly developing world and would like to contribute to a more secure environment.

I like to keep myself relevant by solving Capture The Flags on HackTheBox and working through PortSwigger Web Security Academy labs — publishing 250+ detailed writeups along the way. I also build open-source security tools like an XSS Scanner and an HTTP Request Smuggling Detector to sharpen my practical skills.

I would like to improve myself within the Cyber Security field in order to become a professional Penetration Tester. I always keep a close eye on newly discovered vulnerabilities and like to challenge myself with unsolved weaknesses. I am someone who wants to make the world a more secure place, even if it goes unnoticed.



Background

Driven by Curiosity, Proven by Labs.

I focus on turning complex security theory into hands-on execution. My approach is simple: detect, exploit, report, and defend.


Stats

+ Top 20% TryHackMe

+ 250+ Security Writeups

+ 8+ Custom Python Tools


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Portfolio

Case Studies

Offensive Security

Context-Aware XSS Scanner

Custom Python tool for automated, low-false-positive XSS detection.

  • Problem: Generic XSS scanners flag reflections that never actually execute.
  • Action: Built a scanner using raw TCP/SSL sockets with separate payload logic for HTML, attribute, JS, DOM, and AngularJS contexts, verified via Playwright.
  • Outcome: Confirms exploitability in a real browser before reporting — cutting false positives significantly.
Protocol-Level Testing

HTTP Request Smuggling Detector

Identifying CL.TE / TE.CL desync vulnerabilities at the raw request level.

  • Problem: Standard HTTP libraries auto-normalize malformed headers, making desync attacks impossible to craft.
  • Action: Built a raw-socket tool to send deliberately malformed CL.TE, TE.CL, TE.TE, and CL.0 requests.
  • Outcome: Detects front-end/back-end parsing disagreements that standard scanners miss entirely.
Specialties

Web App Pentesting

SQL/NoSQL Injection, XSS, CSRF, IDOR, HTTP Request Smuggling, Nmap Scripting (NSE), Burp Suite.

Network & Recon

Traffic Analysis (Wireshark), Nuclei, Service Enumeration, Vulnerability Reporting.