Information on viruses

With the Virus List button in the standard Panda Antivirus button bar, you can access the list of viruses detected by Panda Antivirus. You can obtain detailed information on each virus in the list by selecting it.

In the Show section you can choose among viewing all the viruses, viewing only those viruses which contaminate files, viewing those which infect the boot sector, the so-called macro viruses or a list of the most common viruses. Depending on the option you choose, you will see some or other viruses in the list.

You can indicate the name of a virus in Search for viruses to find a specific virus more easily. With this same purpose in mind, the virus list is shown in alphabetical order.

By selecting a virus from the list, you will see detailed information on it in the Information on viruses section. Among the information shown are the: name and alias, origin, size of the virus, the date it was detected, areas it infects and whether or not it can be correctly disinfected. As additional information, you will also be able to read whether the virus has specific characteristics, among which are included:

• Resident: when the virus is executed, it reserves a small part of the memory and installs itself in it in order to contaminate your system progressively from there.

• Stealth: is a technique used by some resident viruses. It consists of camouflaging the changes the virus makes in the files it infects. When a person tries to view one of the characteristics of the file modified by the virus, this one, which is resident in memory, intercepts the consultation and offers the information previous to the modification.

• Encrypted: viruses that have this characteristic are capable of encrypting themselves in a different way each time they infect a file. This way, it is impossible to find the virus using a string search.

• Overwrite: Overwriting viruses, which may be resident or non-resident, overwrite the file they infect. This file then becomes useless. The size of the file does not change unless the size of the virus is greater than that of the file. The only way to remove these viruses is by deleting the infected file and putting an uninfected copy in its place.

• Polymorphic: Polymorphic viruses are advanced versions of encrypted viruses. They are capable of changing their method of encryption from one generation to the next. Thus, there is no part of the virus which remains unchanged.

• Companion: Companion viruses are those that, in order to contaminate an EXE file, create a COM file with the same name and with the hidden attribute enabled. The virus is resident in the cited COM file. If there are two files with the same name and EXE and COM extensions, the MS-DOS operating system will first execute the one with the COM extension. This is how this type of virus propagates itself; when an attempt is made to run a program (an EXE file), what is really executed is the virus (COM file) that is then loaded in the memory, and which will typically execute the EXE file immediately afterward so that the user will not suspect anything.

The Version button brings up a window containing information on the virus file. The information it offers is:

• Number of viruses: indicates the number of viruses detected by the virus file.

• Version: indicates the version of the virus file. This version makes reference to the different technologies which are implemented in the file. It may be that very new releases of the virus file cannot operate properly with old versions of Panda Antivirus; that is why it is important to display this information.

• Date: the date on which the virus file was generated.

• Time: the time at which the virus file was generated.

• Size: indicates the size of the virus file.

The Print button will enable you to obtain a printed copy of the information on the virus whose information is being displayed.