CVE 2010-3563
Unspecified vulnerability in the Deployment component in Oracle Java SE and Java for Business 6 Update 21 allows remote attackers to affect confidentiality, integrity, and availability via unknown vectors. NOTE: the previous information was obtained from the October 2010 CPU. Oracle has not commented on claims from a reliable researcher that this is related to "how Web Start retrieves security policies," BasicServiceImpl, and forged policies that bypass sandbox restrictions.
See the 
CVE page on Mitre.org
for more details.
