Trojan, or Surprise Virus

There are many types of computer viruses. Some are only part of the program, others are themselves full-fledged and useful applications. This type includes the Trojan program. As a rule, it is intended for introduction into a computer system. Once introduced, the Trojan either sends the information to the offender from the infected computer, or destroys the system from within and uses it as a "crime tool". A vivid example of such a virus can be called the program waterfalls.scr, which is masked under the screensaver.

The Trojan program was named in honor of all the famous wooden horse, with the help of which the Greeks captured and destroyed the impregnable Troy. Like the Trojan horse, the program with the same name looks like a harmless and useful gift, but in reality it turns out to be a cunning virus-surprise. Before installation, it is almost impossible to recognize such a virus. Some Trojans, even after installation, continue to perform the functions of the program under which they were disguised. This virus can not multiply, but by launching it, the user always resumes destructive activity in his computer. Almost all viruses of this type consist of a client and a server. The server is injected into the infected system, and the client is being used by the criminal Th to manage it.

The Trojan has six types of malicious activity. Some viruses open remote access to the criminal, others simply destroy data, download additional pests, copy "fake" links to paid registration sites, disable antiviruses and perform DDoS attacks. If the infected computer is connected to the modem Internet, the Trojan makes phone calls, after which the user's account "loses" a considerable amount.

Trojan horses and protection against them

There are several signs on which the infection is determined by the trojan. First of all, you should pay attention to the autorun registry. The "unauthorized" program that appeared there may turn out to be a virus. The infection is indicated by unintentional downloading of games, applications or videos, as well as arbitrary creation of screenshots. During the virus launch, the computer itself can reboot. The Trojan can run video or image viewing, open and close the drive console, or shut down the computer at will.

Because of the abundance of forms and types of a single way to combat the Trojan does not exist. If the system has infected, it is worth clearing the folder with temporary Internet files, and then scan the system with antivirus software. If an object detected by the antivirus is not deleted and is not cleaned, you can find and remove it manually. But with total infection, only the reinstallation of the operating system will help.

One of the newest viruses is called Qhost. This type of Trojan is a modified Windows file of 2600 bytes in size. The new virus blocks the user's transition to certain sites and requests to selected servers. Blocking is carried out by adding to the file a trojan with the host name of the list of "forbidden" sites. To disinfect such a virus, just edit this file in the Notepad program, and then scan the system with an antivirus program.