Browser hijacking Some adware uses Sear4m.xyz to cause a user to click on Sear4m.xyz ads. Once Sear4m.xyz is installed, it changes the default DNS settings of browsers like Mozilla Firefox, Google Chrome, and Internet explorer, and often redirect to various fake websites which are often laiden with viruses. Searchassist is a browser hijacker which piggybacks on other downloads from untrusted websites. It will change the new tab homepage to searchassist.net and opens searchassist on browser start-up. It is stubborn, and if not uninstalled, will repeatedly change the browser tabs and homepage settings. It works with Firefox, Safari, Chrome, and Internet Explorer, though
HTTP cookie allow sharing of cookies between servers by default. However, the newer standard, RFC 6265, explicitly allows user agents to implement whichever third-party cookie policy they wish. Most browsers, such as Mozilla Firefox, Internet Explorer, Opera, and Google Chrome, do allow third-party cookies by default, as long as the third-party website has Compact Privacy Policy published. Newer versions of Safari block third-party cookies, and this is planned for Mozilla Firefox as well (initially planned for version 22 but postponed indefinitely). Advertising companies use third-party cookies to track a user across multiple sites. In particular, an advertising company can track a user