Malware, short for malicious software, is any program or code created to harm a device, steal information, spy on users or give attackers unauthorized control. It is an umbrella term covering many specific types.
Why it matters
Malware causes data theft, financial loss, downtime and hijacked resources. It typically arrives through phishing attachments, malicious downloads, compromised websites or unpatched vulnerabilities. For site owners, injected malware can also get a domain blocklisted by browsers and search engines, which looks like an outage to visitors.
Example
A compromised WordPress plugin adds a hidden script that redirects mobile visitors to a scam page. The owner never sees it, but a blocklist check or search warning reveals it.
Common mistakes
- Believing only Windows PCs get malware. Phones, servers and websites are all affected.
- Running antivirus once and never updating or patching.
- Cleaning the visible symptom without finding the entry point, so reinfection follows.
Related
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