A browser hijacker is software that changes a web browser’s settings without proper consent. It may replace the default search engine, rewrite the homepage, inject new extensions, or redirect traffic through unwanted pages and ads. Some hijackers are bundled with free downloads, while others arrive through malicious installers, fake updates, or deceptive websites.
In cyber security, browser hijackers matter because the browser holds search habits, saved logins, cookies, and session data. By controlling search and navigation behavior, an attacker can push users toward phishing pages, generate ad revenue, or pave the way for credential theft and account takeover. Defenders look for unexpected browser policy changes, unfamiliar extensions, altered proxy settings, and repeated redirects. Good protection includes using trusted software sources, limiting admin rights, monitoring browser artifacts, and removing suspicious add-ons promptly.