Types of Malware Explained: Virus, Worm, Trojan, Ransomware
Malware (malicious software) comes in distinct families that differ by how they spread and what they do. Knowing the differences — virus vs worm vs trojan vs ransomware — is fundamental CyberOps knowledge and a guaranteed interview topic.
The main families
| Type | How it behaves |
|---|---|
| Virus | Attaches to a file; spreads when that file runs |
| Worm | Self-propagates across networks with no user action |
| Trojan | Disguised as legitimate software you install willingly |
| Ransomware | Encrypts your data, demands payment |
| Spyware | Secretly collects information |
| Rootkit | Hides deep in the OS to conceal other malware |
How it's detected
Endpoint protection (EDR) spots malicious behaviour; signature and hash matching identifies known samples; sandboxes detonate suspicious files safely to observe them. SOC analysts investigate malware alerts daily — the analysis skills are central to CyberOps.
Frequently asked questions
What is the difference between a virus and a worm?
A virus needs a host file and user action to spread; a worm self-propagates across networks automatically without any user action.
What is a trojan?
Malware disguised as legitimate software — you install it believing it's safe, and it then executes its malicious payload.
How is malware detected?
Through endpoint detection (EDR), signature and file-hash matching against known malware, and sandbox analysis of suspicious files.
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