Binary Exploitation (Pwn)

CTF pwn challenge writeups by event and year

Binary exploitation writeups from Google CTF, DEF CON, picoCTF, HackTheBox CTF, and more. Organized by year and event.

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2025 Challenges

Google CTF 2025

Google CTF 2025

RET2WIN

Easy

Category: Pwn · Points: 120 · Solves: 654

Basic x64 stack buffer overflow. Overwrite the saved return address (RIP) on the stack to jump to a hidden `win()` function that prints the flag.

Stack OverflowBuffer Overflowx84_64ret2win

Writeup →

HTB Cyber Apocalypse 2025

HTB Cyber Apocalypse 2025

Chatbot

Medium

Category: Pwn · Points: 280 · Solves: 145

A console chatbot vulnerable to format strings and stack overflows. Leak stack values (canary & libc addresses) via format string, then trigger stack overflow to perform a ret2libc payload.

Format StringStack Canary Bypassret2libcASLR Bypass

Writeup →