Computer viruses are the type of malware that can infiltrate
the code of other applications and reproduce by copying itself. They can also
distribute their copies through various communication channels.
computer virus
A computer virus is created to reduce the functionality of
the hardware and software structures of computing devices: deleting files,
corrupting data, blocking the user's work. Exposure to infections can be not
only destructive, but also annoying, as they slow down the operating system,
cause crashes and sudden reboots, reducing free memory capacity. Those viruses
were often created by researchers or computer hooligans without any selfish
intent.
Users often use the term computer viruses to refer to the
entire range of malicious programs, although this is not always the case.
Today, computer viruses that infect files are very rare, unlike, for example,
Trojans or backdoors.
Classification of computer viruses
Computer viruses can be systematized by the platforms to
which they are directed and for which operating systems they are directed
(Microsoft Windows, Linux, etc.), as well as by the objects of infection (boot,
file, script), by the technologies used , by programming languages .
Furthermore, viruses can be divided by their mode of action:
• Overwrite
. Such infections write themselves in place of the source code without changing
the file name. As a result, an infected application simply stops working and a
malicious program runs in its place.
• Parasite
. These viruses write their code anywhere in the executable file. The infected
program runs totally or partially.
• Companion
viruses . After copying themselves, they rename or move the original file.
Ultimately, the legitimate program works, but only after the virus code runs.
• Virus
infected links . This malicious code changes the location address of the
software to its own. In this way it forces the operating system to run it
without changes to the code of other applications.
• Destructive
viruses . This can include malicious elements that simply damage the original
code of a program or its components in order to disable them.
Objective of the incident
Every computer can be the target, but most viruses are
targeting the Windows platform . New computer viruses capable of replicating
and infecting executable files are rare today. Their spread peaked in the late
1990s. With the spread of computer networks and Internet files, viruses quickly
began to lose relevance, as there are easier ways to spread malware.
Origin of the threat
Several main ways of infecting computer systems with file
viruses are identified.
• Removable
media . It can be ready-made floppy disks, optical drives, USB sticks. Floppy
disks are not relevant today, but mobile phones and smartphones, digital
cameras, camcorders and players have joined the ranks of carriers of dangerous
information.
• Through
local area networks . The virus, upon entering a file server, quickly spreads
to other computers.
Risk analysis
Any user's computer can become a victim of viruses. The
damage caused ranges from a simple system slowdown to complete machine failure
and file corruption. Every year new types of viruses emerge that can avoid the
usual protection methods.
