The original Critical Patch Update for Java SE was scheduled on February 19th, but Oracle decided to accelerate the release of this Critical Patch Update because active exploitation “in the wild” of one of the vulnerabilities affecting the Java Runtime Environment (JRE) in desktop browsers, was addressed with this Critical Patch Update.
In addition to a number of security in-depth fixes, the February 2013 Critical Patch Update for Java SE contains fixes for 50 security vulnerabilities.
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For Java users:
It is advised to uninstall all previous versions, before updating.