Malware
Adware
Also known as: Advertising-supported malware, PUP adware
Definition
Software that automatically displays, injects, or redirects to advertisements, often bundled with free software and frequently tracking user behavior.
Examples
- Bundled "free PDF reader" installers that add unwanted browser toolbars.
- Fireball, an adware family that turned browsers into ad-revenue zombies.
Related terms
Malvertising
The use of online advertising networks to distribute malware, exploits, or scams via legitimate-looking ads served on trusted websites.
Browser Hijacker
Software that alters browser settings without user consent to redirect traffic, change the homepage and search engine, or inject unwanted ads.
Potentially Unwanted Program (PUP)
Software that is not strictly malicious but installs without clear consent, behaves intrusively, or degrades user experience — for example, bundled toolbars, adware, or aggressive optimizers.
Greyware
Software that sits in a grey area between legitimate and malicious — annoying, intrusive, or risky, but not clearly designed to harm the user.
Trackware
Software that monitors and reports on user activity — sites visited, apps used, keystrokes, or location — typically for advertising, analytics, or stalking.
Malware
Any software intentionally designed to disrupt, damage, or gain unauthorized access to computers, networks, or data.