A browser hijacker is a type of malware that takes control of your web browser and alters its behaviour without your knowledge or consent. Once installed, it changes settings like your homepage, search engine, or new tab page, usually redirecting you to attacker-controlled websites or search results.
Browser hijackers work by:
- Installing extensions or plugins that modify browser functionality
- Changing registry entries or configuration files on Windows
- Modifying preference files on Mac systems
- Injecting ads into web pages you visit
- Capturing your browsing data or search queries
The primary motivation is financial. Attackers profit through advertising revenue, affiliate commissions when you click their links, or data harvesting. Some hijackers also track your online activity to sell behavioural data to third parties.
Common signs you have a browser hijacker include: unexpected toolbars appearing, constant pop-up ads, search results from unfamiliar search engines, or a homepage you did not set. Your browser may also feel sluggish, as hijackers consume system resources.
Browser hijackers often arrive bundled with free software downloads, fake browser update prompts, or malicious advertisements. They can spread across multiple browsers on the same device.
To protect yourself: use reputable download sources, read installation prompts carefully and uncheck bundled software, keep your browser and operating system updated, and run regular antivirus scans. If infected, remove suspicious browser extensions, reset your browser settings to defaults, and use security software to scan for remaining malware. Consider switching browsers entirely if the hijacker persists.