December 23, 2011

Join 2 executable files on one (II of IV)

Following the tutorials about attach some files with others, and we started with this, we continue with a much more easy to use, and above all, much more powerful.
This time use IExpress, a utility that comes by default in Windows, though hidden, and that very few people know. The main use of this wizard is to create self-extracting archives and self-installable. And that is what we create. Before opening the program, we will choose to join the 2 executables. For this example we will use calc.exe (calculator) and virus.exe (not a real virus, is a file with that name that contains nothing. Every one can use the files you want under your responsibility).
To start, go to Start, open the run menu and type IExpress. A wizard will launch. On the first screen, choose Create new Self Extraction Directive file, since we want to do is create a new one, and click Next.

Here we ask what we want to make the executable created: run 2 or more files in the installation, just extract the files or just create compressed files. For this practice we choose the first option.

On the third screen will give a name to the installation package. We write Calculator.

December 20, 2011

How to trace spam email

In this post we will try an interesting topic: the spam that continually recieve to our email. Let's use an example a mail that I receive, and indicate that you should update the data of a bank to unlock your account.

upload images

For starters we see several details that can make us suspect: in the first paragraph tells us that there was a problem with an account of Bankia (spanish bank), however in the origin and the rest of the email it told that is from BBVA (another spanish bank).

Viewing the source code of the message, see the IP from which the mail, in this case

December 18, 2011

What information can find our web browser about us or our system?

Many times when we went to a web page, we see a banner that shows the information about our equipment or signage in the language or geographical area from which we connect. For example, a banner with our IP and our ISP or Google advertisements only for the city from we are connecting, etc ...
The best thing to protect part of our privacy is to use a proxy, as published recently, or some anonymous surfing web.

But ... what can find my web browser about me and my computer?

A good website for these data is On this page we perform several tests to check your privacy. This is the main page, in which different parts are distinguished: in the center publish news about web sites that speak of it. On the right there are various tests to perform, and that is the part that interests us.

December 10, 2011

Multiproxy chains to leave no trace in Internet

A proxy is a program that makes Internet access to your computer instead. It's like somewhere between a computer connected to the Internet and the server you are accessing. When we surf through a proxy, we're not actually going directly to the server, but we make a request on the proxy and it is he who connects to the server that we want to access and returns the result of the application. (Wikipedia)
There are several programs to perform this task. At this time we will do using SocksChain, which you can download from here.
Once installed and running, we see that the interface is this:
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December 9, 2011

ALTERNATE DATA STREAMS, or how to hide a file inside another file

We start talking about what is and how it works. Essentially, the "Alternate Data Streams" (ADS) are files within another file. You can think of a file as an ordered sequence of bytes accessed by a name. In NTFS System (New Technology File System) this is the data stream that comes from opening the file normally. However, NTFS has the ability to save alternative flows next to the main data by specifying a name for themselves.
Now let's do a simple test. To begin, go to command prompt and run the following commands:

Echo text1> file.txt
Echo text2> final.txt
(Create 2 files with the given text)

Type final.txt> file.txt: final.txt
(The file file.txt contains the file final.txt)

More <file.txt: final.txt
(We see the contents of final.txt)

Welcome to LineSec

This blog was created with the idea of ​​being a page where a beginner and new to the world of computer security publish his works and ideas, and share with the rest of the world his knowledge.
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