Java for OS X Lion 2012-001 and Java for Mac OS X 10.6 Update 7

Multiple vulnerabilities exist in Java 1.6.0_29, the most serious of which may allow an untrusted Java applet to execute arbitrary code outside the Java sandbox. Visiting a web page containing a maliciously crafted untrusted Java applet may lead to arbitrary code execution with the privileges of the current user.
These issues are addressed by updating to Java version 1.6.0_31.
Further information is available via the Java website at http://www.oracle.com/technetwork/java/javase/releasenotes-136954.html

http://support.apple.com/kb/HT5228