The plugin functionality in Sun Java SE 6 before Update 15 does not properly implement version selection, which allows context-dependent attackers to leverage vulnerabilities in "old zip and certificate handling" and have unspecified other impact via unknown vectors.
http://www.vupen.com/english/advisories/2009/3316
http://www.vmware.com/security/advisories/VMSA-2009-0016.html
http://www.securityfocus.com/archive/1/507985/100/0/threaded
http://security.gentoo.org/glsa/glsa-200911-02.xml
http://secunia.com/advisories/37460