Apple Safari allows remote attackers to discover a redirect's target URL, for the session of a specific user of a web site, by placing the site's URL in the HREF attribute of a stylesheet LINK element, and then reading the document.styleSheets[0].href property value.
https://euvd.enisa.europa.eu/vulnerability/EUVD-2010-0345
http://www.vupen.com/english/advisories/2011/0552
http://www.vupen.com/english/advisories/2010/2722
http://www.ubuntu.com/usn/USN-1006-1
http://www.mandriva.com/security/advisories?name=MDVSA-2011:039
http://secunia.com/advisories/41856
http://nomoreroot.blogspot.com/2010/01/little-bug-in-safari-and-google-chrome.html