Opera before 10.10, when exception stacktraces are enabled, places scripting error messages from a web site into variables that can be read by a different web site, which allows remote attackers to obtain sensitive information or conduct cross-site scripting (XSS) attacks via unspecified vectors.
osvdb.org/60527
secunia.com/advisories/37469
www.opera.com/docs/changelogs/mac/1010/
www.opera.com/docs/changelogs/unix/1010/
www.opera.com/docs/changelogs/windows/1010/
www.opera.com/support/kb/view/941/
www.securityfocus.com/bid/37089
www.vupen.com/english/advisories/2009/3297
oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A6385