CyberGlossary

Malware

Browser Hijacker

Also known as: Search hijacker, Homepage hijacker

Definition

Software that alters browser settings without user consent to redirect traffic, change the homepage and search engine, or inject unwanted ads.

A browser hijacker modifies the configuration of a web browser to monetize or surveil the user. Typical changes include forcing a new homepage, replacing the default search engine, installing rogue extensions, redirecting search results to affiliate or scam sites, and injecting ads into legitimate pages. While some hijackers are nuisance-level adware, others harvest browsing data, steal cookies and credentials, or deliver further malware. Distribution is usually through bundled installers, fake updates, and malvertising. Defences include reviewing installed extensions, blocking unsigned or low-reputation extensions, enterprise browser policies, using reputable software sources, and resetting the browser to defaults after infection.

Examples

  • Extensions that change the default search engine to a low-quality ad-driven service.
  • Bundled toolbars that redirect new tabs and inject sponsored links into search results.

Related terms