pwnmedium

Evil Corp

hackthebox

Task: 64-bit PIE binary with wide character API (fgetws, wchar_t) and adjacent mmap regions (RW + RWX). Solution: Exploit wchar_t to char16_t type confusion to overflow into RWX region, inject shellcode at fixed address, then stack overflow in login to redirect execution.

$ ls tags/ techniques/

shellcode mmap rwx pwn pie-bypass stack-overflow wchar type-confusion fgetws no-canary map-fixed

mmap_overflow_to_rwxwchar_type_confusionstack_bof_ret2fixedshellcode_encoding_via_wcharnull_byte_via_fgetws

Analysis

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$ python3 exploit.py --target 192.168.1.1 --port 8080
[*] Connecting to target...
[+] Shell obtained!

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