Viruses and Trojans
The aim of the virus, most often it is destructive, but not always. Sometimes they are masterpieces of programming, pursuing the challenge to learn or to demonstrate the security flaws in operating systems or the Internet. Scheduled assembly (machine code) or other high-level languages, viruses are becoming more powerful and affecting more files, such as the OUTLOOK. PDF Worm, the first worm which is presented in a PDF (Portable Document Format), known Adobe Acrobat format. Although clearly, the latter at present can be seen as a virus laboratory designed to be more a proof of concept.
When a virus infection begins, the code comes into action, depending on its programming, will be more or less destructive, causing problems for the user's computer system. We sometimes behave in a similar way to biological, although there is a very clear difference. Computer viruses are always introduced into the system when the user runs. Therefore, if we have an updated antivirus and we refrain from opening files of suspicious provenance unknown, we can be safe from these, at least in a very high percentage. The biological is different, we all know that we can perfectly and caring for the simple fact of breathing polluted air conditioning we can enter a virus. But the creators of these viral software, sometimes we can find works of "social engineering" that encourage the user to run a virus virtually without realizing it, for example when receiving an email from a person known saying "hello how are you, command you this for your comments, "we have a situation known Sircam worm.
However, a trojan is a program that creates a backdoor (ie provides the possibility of unauthorized access) to the computer equipment of the victim, so that it opens a port (or communication channel) where can access your system. As such, they often find themselves glued to other programs through various utilities specifically designed for it, and concealing its real function through the appearance of a program that apparently works well, as it could be a simple screensaver.
Some of them even allow you perform functions that otherwise would not be feasible. There is an analogy in its operation (which disagrees with its origin and intent) with remote-control programs legitimate or legal. In fact they differ only in how to install and that invariably do not appear in the system tray or in the status bar.
They consist of two parts: the client and server. The server is the one who allows intruders entering indeed to our computer, and have even the possibility of sending our IP address to any email address, a mailing list, the ICQ, or an IRC channel. To get rid of them, the best thing is common sense: Do not accept gifts to strangers, nor enforceable whatsoever.
A Trojan Horse (or Trojan) is a program apparently useful, novel, or attractive containing hidden functions that allow, for example, get user privileges (provided that the program is implemented), assuming an enormous security problem. Usually a Trojan horse has no effect without the cooperation of involuntary user to whom it is directed. The Trojan horses are usually installed by the users themselves inadvertently or by intruders who have gained access without permission on through other means. While conceptually some authors believe that viruses are not as such, they can perform destructive actions as some viruses. At consist of two programs, server and a client. The server is for example our team (to get an idea) and the customer's who tries to "enter" into our computer, once it has succeeded, according to the characteristics of this Trojan horse, you can delete files from a hard drive , Format, open the CD-ROM drive, capturing our desk, of what type, including Trojans that there are "copy" file. PWL that is where the Windows system saves passwords and send an email to electronic. These "Trojan Horses" are often contained in executable programs and through chat, for example mIRC we can send this type of "programmes", or through ICQ. Normally usually stay resident in memory and introduce code in the Windows registry so that every time that ignited our team can be activated.
Much has been written about how to eradicate worms, Trojans or backdoors of a system. In the case of home users of the councils should be given more caution is needed to understand something substantial Windows Registry and other subtleties. The only thing we can grasp is currently the preventive work is a matter of three at least. In conclusion, more experienced users I recommend carefully evaluate the usefulness of the following advice:
"Be careful always reviewing what programs are those in the Windows Start and put special care if they have hidden attribute its role and has no input justification."
