What is malware and what are the main types?
Short answer
Malware is software designed to harm or gain unauthorized access to a device or network. Common types include ransomware, information stealers that take passwords and session cookies, trojans disguised as legitimate apps, spyware, and botnet malware that turns devices into tools for other attacks.
The details
Most malware arrives through phishing, malicious downloads, fake software updates and unpatched systems. Updates, careful downloading, least privilege and endpoint protection block most of it.
Useful next reads and tools
Terms explained
- Malware
- Malware is any software designed to harm, spy on or gain unauthorized control of a device, network or account.
- Ransomware
- Ransomware is malware that encrypts or steals data and demands payment to restore access or prevent publication.
- Least privilege
- Least privilege means giving each user, service or AI agent only the access it needs to do its job, and no more, for only as long as it needs it.
- Patch management
- Patch management is the process of finding, prioritizing, testing and installing software updates that fix security flaws.
- Phishing
- Phishing is a fraudulent message, usually email, that impersonates a trusted sender to trick people into revealing credentials, paying money or running malware.
Sources
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