Sun describes a flaw at: http://sunsolve.sun.com/search/document.do?assetkey=1-26-103079-1 A vulnerability in the Java Runtime Environment (JRE) with applet caching may allow an untrusted applet that is downloaded from a malicious website to make network connections to network services on machines other than the one that the applet was downloaded from. This may allow network resources (such as web pages) and vulnerabilities (that exist on these network services) which are not otherwise normally accessible to be accessed or exploited.
The list of fixed products with their respective errata is here: https://access.redhat.com/security/cve/CVE-2007-5232