The tabbed browsing feature in Apple Safari 3 before Beta Update 3.0.4 on Windows, and Mac OS X 10.4 through 10.4.10, allows remote attackers to spoof HTTP authentication for other sites and possibly conduct phishing attacks by causing an authentication sheet to be displayed for a tab that is not active, which makes it appear as if it is associated with the active tab.
https://exchange.xforce.ibmcloud.com/vulnerabilities/38460
http://www.vupen.com/english/advisories/2007/3868
http://www.us-cert.gov/cas/techalerts/TA07-319A.html
http://www.securityfocus.com/bid/26447
http://www.securityfocus.com/bid/26444
http://secunia.com/advisories/27643
http://lists.apple.com/archives/security-announce/2007/Nov/msg00003.html
http://lists.apple.com/archives/security-announce/2007/Nov/msg00002.html