Hey, I'm Oleg
Learning pentesting. Writing code. Taking notes along the way.
This is where I document what I learn — mostly security research, some frontend, and a bit of devops.
Browse by category
Pentesting — security tools, techniques, CTF writeups
Cheatsheets — in-depth security reference guides
Frontend — Vue.js, Nuxt, web development patterns
DevOps — shell one-liners, automation, tooling
Cheatsheets
Server-Side Request Forgery (SSRF)
Complete breakdown of SSRF — where to look, types, protocols, filter bypass, cloud metadata, paths to RCE, defenses. Theory, methodology, cheat sheet.
Server-Side Template Injection (SSTI)
Complete SSTI breakdown — detection, engine identification, sandbox escape, per-engine exploitation, blind SSTI, defense. Theory, methodology, cheatsheet.
XML External Entity (XXE)
Complete XXE breakdown — XML entities, DTD, all attack vectors, blind/error-based, bad character bypasses, defense by language. Theory, methodology, cheatsheet.
Recent posts
Arbitrary Object Injection in PHP (PortSwigger Lab)
Recovering leaked source code and injecting a serialized CustomTemplate object whose __destruct deletes an arbitrary file.
Using Application Functionality to Exploit Insecure Deserialization (PortSwigger Lab)
Tampering with the `avatar_link` field in the session object to delete an arbitrary file via the account-delete feature.
Modifying Serialized Data Types (PortSwigger Lab)
Abusing PHP loose comparison by changing the `access_token` type to integer `0` to bypass authentication.
Modifying Serialized Objects (PortSwigger Lab)
Flipping the `admin` boolean inside a PHP-serialized session cookie to gain administrative privileges.
Web Shell Upload via Extension Blacklist Bypass (PortSwigger Lab)
.php is blacklisted, but .htaccess uploads without complaint — we slip our own Apache config in and make the server execute shell.bug as PHP.