The malicious software arrives in different ways, often disguised in the form of software codes, scripts, active content, and other software that seems legitimate. The malware comes in two main forms, and they are the viruses and worms.
Nearly all viruses are assigned to an apparently harmless executable file but when that file is opened, bad things happen. A malicious program may exist on a computer but will not become active until a user opens the infected file/program.
Worms are an independent program that replicates themselves and infects multiple computers on a network. Depending on the type, a worm may be able to disseminate the damage, for e.g., a network worm usually utilizes the computer network to spread and in the event, slows down the network traffic. Hackers prefer worms over viruses to carry out their illegal activities.
Viruses and worms demand different virus protection mechanisms due to their differing qualities. Typically, a virus scanner examines the files in a computer for the signatures of known viruses.
The unique pattern which occurs in all copy of a virus is called as the signature. This patterns are recognized by computer security professionals and are later given to security Websites. The updated patterns are downloaded by Virus scanners to keep their internal pattern files up-to-date.
Three types of practical difficulties are required to be attended in this scheme!
Firstly, if the patterns are wrongly identified then they can appear in uninfected files. For instance, a pattern bearing just the word “Sound” wouldn’t be pretty helpful. The technicians need to find patterns that are different from the viruses.
Secondly, the complexity is purposefully created by the virus writers who safeguard their viruses from being detected, therefore, they engage in secretive techniques. For instance, most viruses get saved on the computers in encrypted form, therefore changing the encryption key as they move from system to system makes the encrypted patterns appear different in every victim’s computer. Latest virus scanners can knock this method both by placing their patterns to explore for the part of the program that decrypts the virus or by duplicating the decryption operation before performing the matching.
Thirdly, the complexity is designed to affect the performance of a computer. Apparently, a virus is attached to a seemingly good executable file and may exist on without spreading until a user opens the infected program. There are thousands of host programs on a computer and scanning all the programs every time will take a long time to finish the virus scanner process. Therefore, virus scanners normally restrict themselves to a modest list of potential hosts. For instance, all externally connecting devices and removable disks are normally scanned whenever they are inserted.
Due to the logical reason worms are independent programs, they are slightly easier to detect. They remain in a file of their own somewhere and the challenge is to construct the file in such a way that the system will automatically eliminate it. The restrictions set limits on such properties as to find the file in its original form. The scanner will check the known places and then implement the similar pattern-matching techniques that were used for viruses.
Today, scanners are rightly directed to hunt malware. Mostly, they arrive in an email to the victims’ machine, so a virus scanner can be set up to verify the legitimacy of the incoming emails. When a worm is detected, without any delay it can be removed from the message. It is equally important to remove the worm from the outgoing email from the infected computer.
The cleanup process is pretty straightforward. For instance, if a software manufacturer gave an infected file, it should be succeeded with a clean copy. In the case of personal files which cannot be replaced, the infected portion can be overwritten with the good files.
The best way to protect your system or other devices from viruses and worms is to keep your operating system clean and up-to-date by downloading regular security patches and updates.
If you experience any of the above-mentioned signs, your computer is definitely infected with virus or worm. Be sure to install a virus protection software like the Comodo Antivirus to get rid of the virus or worm and prevent future attacks.