Although browsers such as Internet Explorer 8 and Firefox 3 have added a "Privacy Browsing" setting, they still allow Flash cookies to track the user and operate fully. However, the Flash player browser plugin can be disabled or uninstalled, and Flash cookies can be disabled on a per-site or global basis. Adobe's Flash and (PDF) Reader are not the only browser plugins whose past security defects have allowed spyware or malware to be installed: there have also been problems with Oracle's Java.