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Virus 🔴 Attack

A computer virus is a type of malicious software (malware) which, once executed, reproduces itself by inserting copies of itself into other programs or files on a computer. It can also modify or destroy data.

Features

CATEGORY : 🔴 Malicious software (malware)
FREQUENCY : 🔥🔥🔥🔥
DANGEROUS : 💀💀💀
DIFFICULTY OF ERADICATION : 🧹🧹🧹

Common features of viruses

Auto-replication A virus copies itself into other files or programmes.
Propagation It is generally spread by removable media (such as USB sticks), Internet downloads or email.
Activation The virus is often activated when the user runs the infected program.
Potential damage It can cause damage ranging from file corruption to unauthorised access to sensitive data.

How it works

Initial infection The virus attaches itself to a legitimate host program or file. Infection can occur by opening a malicious attachment, downloading compromised software or visiting an infected website.
Activation Once the host program or file has been executed, the viral code is activated. Some viruses remain inactive until specific conditions are met, such as a specific date or a particular action by the user.
Propagation After activation, the virus replicates itself by attaching itself to other programs, files or systems, facilitating its spread via networks, removable media or file exchanges.
Payload execution The virus carries out the actions for which it has been programmed, such as corrupting data, stealing information, monitoring the user's activities or disrupting the system.

Types of virus

File viruses infect executable files.
Boot sector viruses (boot): infect the boot sector of a hard disk or removable media.
Macro viruses These attack office application files (Word, Excel, etc.) containing macros.
Resident viruses Viruses are installed in the computer's RAM, allowing the virus to run and spread even after the host program has been closed.
Polymorphic viruses They change their code with each infection, making them harder to detect by anti-virus software.

💥 Consequences of viruses

Loss or corruption of data Viruses can alter, delete or render inaccessible essential information, causing significant operational disruption.
Interruption of services Viruses: by affecting system performance, viruses can cause breakdowns or slowdowns, impacting business continuity.
Damage to reputation A virus infection can damage the confidence of customers and partners, especially if sensitive data is compromised.
Financial costs The cost of data recovery, system restoration and additional security measures can be considerable.
Legal risks Unauthorised disclosure of personal data may result in legal sanctions and prosecution.

💉 Protection and remedies

Using antivirus software Install and regularly update antivirus software.
Regular back-ups Backups: make backups of your data to avoid loss in the event of infection. See article on backup 3-2-1.
Software updates Make sure all your software is up to date to correct any errors. vulnerabilities.
Raising user awareness Make users aware of the risks of opening suspicious files or links.