Malware is malicious software designed to damage systems, disrupt operations, steal data, or gain unauthorized access to devices and networks. It is intentionally harmful; software that causes accidental damage without malicious intent is not usually classified as malware.

Core idea

  • Malware is any program or code created with the purpose of compromising the confidentiality, integrity, or availability of an information system.
  • It can infect computers, phones, servers, or entire networks, often without the user realizing it is there.

Common types

  • Viruses: Attach themselves to legitimate programs or files and spread when those are run, often damaging or altering data.
  • Worms: Self-replicating programs that spread across networks without user action, consuming resources and potentially delivering other payloads.
  • Trojans: Malicious code disguised as legitimate software to trick users into installing it, then opening a backdoor or stealing data.
  • Ransomware: Encrypts files or locks systems and demands payment to restore access.
  • Spyware: Secretly monitors user activity and steals information like passwords or browsing habits.
  • Adware: Aggressively displays unwanted ads and may track user behavior; some forms are considered malicious when they undermine privacy or control.

How malware spreads

  • Malicious email attachments or links in phishing messages.
  • Infected downloads from untrusted websites, pirated software, or fake apps.
  • Exploiting software vulnerabilities in outdated operating systems, browsers, or plugins.
  • Compromised removable media (USB drives) or local network propagation.

What malware does

  • Steals sensitive information such as passwords, financial data, or business secrets.
  • Disrupts or destroys data and systems, from deleting files to wiping entire disks.
  • Takes control of devices to use them in botnets for spam or distributed denial-of-service (DDoS) attacks.
  • Extorts victims through ransomware by locking data until a ransom is paid.

Staying safe

  • Keep operating systems and applications up to date with security patches.
  • Use reputable security software and enable real-time protection.
  • Be cautious with email attachments, links, and downloads, especially from unknown senders or unofficial sources.
  • Regularly back up important data so ransomware or other destructive malware cannot cause permanent loss.

Information gathered from public forums or data available on the internet and portrayed here.