VPN Guide
What Is Malware?
Malware is any software designed to damage, disrupt, or gain unauthorized access to a computer, phone, or network. The term covers everything from old-school viruses to modern ransomware and spyware. Understanding the categories helps you recognize threats and choose the right defenses.
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See all VPN reviewsCompare providersThe Main Types of Malware
Virus — code that attaches itself to a legitimate file or program and spreads when that file runs. Mostly historical now; classic file-infectors are rare in 2026.
Worm — self-spreading malware that propagates over networks without user action. WannaCry (2017) is a famous example.
Trojan — malware disguised as legitimate software. The user willingly installs it. Most modern desktop malware falls in this category.
Ransomware — encrypts your files and demands payment for the key. See our dedicated ransomware guide.
Spyware — silently collects information (keystrokes, screenshots, credentials).
Adware — bombards you with ads, often bundled with free software.
Rootkit — hides itself deep in the OS to maintain persistent access.
Botnet client — turns your device into a node in an attacker's network, often used for DDoS or spam.
How Malware Reaches Your Device
The most common 2025–2026 infection vectors:
- Phishing emails and SMS with malicious attachments or links — see our phishing guide
- Cracked / pirated software bundled with trojans
- Malicious browser extensions
- Sideloaded Android APKs from non-Play sources
- Drive-by downloads from compromised websites (rarer now thanks to browser sandboxing)
- USB drives in targeted attacks
- Software supply-chain compromises (e.g., the SolarWinds incident)
MacOS and iOS face less malware than Windows and Android, but they are not immune.
Signs You May Be Infected
- Sudden slowdowns or fan running constantly
- Pop-ups and browser redirects you didn't trigger
- Unfamiliar programs in your task list or startup items
- Antivirus disabled itself
- Friends report receiving messages you didn't send
- Unexpected logins to your accounts
- Files renamed or with new extensions (a ransomware sign)
If you suspect infection, disconnect from the network, run a full scan with a reputable antivirus (or Microsoft Defender on Windows), and change passwords from a known-clean device.
How to Protect Every Device
On Windows: Keep Defender enabled, install updates promptly, and avoid pirated software. See our best antivirus for Windows picks.
On Mac: Trust XProtect and Gatekeeper, install from the App Store when possible. See antivirus for Mac.
On Android: Stick to the Play Store, run a third-party scanner like Bitdefender, disable 'install unknown apps' for browsers. See antivirus for Android.
On iPhone: Keep iOS updated, use a VPN with threat protection on public Wi-Fi, never install configuration profiles from untrusted sources. See iPhone antivirus.
Universally: Use a password manager, enable 2FA, and pair your antivirus with a reputable VPN. See our top VPN reviews.
Frequently Asked Questions
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Reviewed Sep 2026 · Public-source research · First-party tests appear on review pages when dated results are published · Verify details on provider sites. Editorial policy & scoring