Since August 2012 updates for Java (and especially Java Runtime Environment, which is what you actually need) must now be downloaded direct from Oracle:
(which is for Java 7)
Further information here:
and their FAQ’s:
The recently released Java 7 Update 11 has been blocked by Apple through its XProtect anti-malware feature in OS X.
Oracle issued the latest update to Java earlier this month to fix a serious zero-day security flaw. The threat was so serious that the U.S. Department of Homeland Security had recommended that all Java 7 users disable or uninstall the software until a patch was issued.
Apple took action on its own and quietly disabled the plugin through its OS X anti-malware system. And as noted by MacGeneration on January 31, Apple has again updated its OS X XProtect list, this time to block Java 7 Update 11.
Because Oracle has yet to issue a newer version of Java that addresses any outstanding issues, Mac users are prevented from running Java on their system.
Over the last few years, Apple has moved to gradually remove Java from OS X. The Mac maker dropped the Java runtime from the default installation for OS X 10.7 Lion when the operating system update launched in 2010. Java vulnerabilities have been a common exploit used by malicious hackers looking to exploit the OS X platform.
Most notably, the "Flashback" trojan that spread last year was said to have infected as many as 600,000 Macs worldwide at its peak. Apple addressed the issue by releasing a removal tool specifically tailored for the malware, and also disabled the Java runtime in its Safari web browser starting with version 5.1.7.
However, if you need the Jave 6 JRE and plug-in, MadMAC0 has posted at
Apple has also posted (Oct 22/12) the approved solution for restoring the Java 6 plug-in:
Interesting article here on why Apple removed Mac browsers’ ability to run Jave Applets:
Oracle on Friday February 1 released a new version reportedly addressing vulnerabilities seen with the last build.
Apple disabled Java 7 through the OS X XProtect anti-malware system, requiring users to have at least version "1.7.0_10-b19" installed on their Macs. The release dated February 1 carries the designation "1.7.0_13-b20," meeting Apple's requirements.
Oracle "strongly recommends" applying the CPU fixes as soon as possible, saying that the latest Critical Patch Update contains 50 new security fixes across all Jave SE products.