The term malware is used to describe any software dangerous for the proper functioning of the PC, which can take control over it and cause damage. The term Malware is constructed from the phrase malicious software.
This type of software is designed intentionally to infiltrate a computer system to cause it to behave inappropriately or to obtain certain information from it.
There are several types of malware: viruses, trojans, worms.
1. Viruses
The virus is a self-executing software, being able to attach itself to other programs or hide in the code that runs automatically when certain files are opened. The virus self-multiplies by attaching itself to other programs or by overwriting programs with its own code.
In order to self-replicate, a virus must have permission to execute code and access the memory area. That is why viruses are often attached to executable files belonging to legitimate programs. If a user launches an infected program, the virus code will also be executed. From the point of view of their behavior when the code is run, viruses are divided into two categories: resident viruses and non-resident viruses.
Nonresident viruses look for other hosts that can be infected, infect them, and take control of those programs. Resident viruses are loaded into memory during execution and transfer system control to the host program.
Effects of virus infection
There are several types of viruses, which have different effects on the behavior of the system.
Parasitic viruses are viruses that attack executable files. The virus is launched when the executable file is launched.
Boot viruses infect the boot sector of hard disks and floppy disks. When the respective virus is activated, it can cause the boot system to malfunction.
2. Trojans
They are programs that infect the system, allowing the system to be taken over by an external user, through the Internet, without approval, allow the theft of passwords, perform destructive operations, or send information packets to a certain target to interrupt the target’s Internet services (Denial of Service) ). When a system sends packets to a certain target to block internet services, this system is considered suspicious, and its access to certain resources can be restricted.
3. Worms
Worms are similar to viruses, the difference between them being represented by the fact that for worms a host file is not necessary for them to multiply. A worm uses the infected system for replication and uses communication between systems to spread.
And the sites can be infected with Malware. Usually a site that is infected is used to infect users who come into contact with it. Search engines use certain criteria to determine if a site hosts or distributes Malware. In these cases, a warning message such as “This site may harm your computer” is displayed on the respective page. In this case, the site is considered an “attack site”.
Learn more about this topic in the article This site can damage to your computer.
Preventive methods
- User education. The user must not open emails from people he does not know. You should also not open links from unknown people, or download applications recommended through suspicious emails. Another recommendation is not to have automatic updates activated, because malware can also be downloaded through it. Upgrades must be chosen personally by the user, from verified sites.
- Installing anti-malware software. These softwares rely on 2 methods to detect and remove malware from systems. The first method, the most widespread, consists in the detection of viruses using a list of virus signatures. The content of the PC’s memory elements (RAM memory, boot sectors) and the files stored on hard disks or floppy drives are examined, and it is determined if a virus signature appears in the antivirus database. The main disadvantage of this method is represented by the impossibility of protection against new viruses, and the need to permanently load the latest version of the database with signatures. The second method is based on the use of an algorithm that detects viruses based on normal behavior. Its advantage is that it can detect new viruses, whose signature is not known.
If you do not want to install such software, you can scan your system using specialized sites that provide computer scanning solutions against malware.
If you want to find out more information or want to avoid such incidents, you can contact an agency SEO to help you.