Google Chrome before 4.0.249.78 sends an https URL in the Referer header of an http request in certain circumstances involving https to http redirection, which allows remote HTTP servers to obtain potentially sensitive information via standard HTTP logging.
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A14247
http://sites.google.com/a/chromium.org/dev/Home/chromium-security/chromium-security-bugs
http://securitytracker.com/id?1023506
http://googlechromereleases.blogspot.com/2010/01/stable-channel-update_25.html