A vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of Sun Java Web Start. User interaction is required to exploit this vulnerability in that the target must visit a malicious page. The specific flaw exists in the useEncodingDecl() function used while checking xml based JNLP files for UTF8 characters. When a user downloads a malicious JNLP file, the data immediately preceding the opening of the xml tag is read into a static buffer. If an overly long key name in the xml header is included, a stack based buffer overflow occurs, resulting in an exploitable condition.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/64536/ZDI-08-009.txt
Source: https://packetstormsecurity.com/files/64536/Zero-Day-Initiative-Advisory-08-09.html