Apple’s patchnotes for the Flashback removal tool:
This update removes the most common variants of the Flashback malware. If the Flashback malware is found, a dialog will notify you that malware was removed. In some cases, the update may need to restart your computer in order to completely remove the Flashback malware.
To improve the security of your Mac, this update also disables the Java plug-in in Safari. For instructions on how to re-enable it, please visit: http://support.apple.com/kb/HT5241.
The patch notes for Leopard Security Update 2012-003:
This update disables versions of Adobe Flash Player that do not include the latest security updates and provides the option to get the current version from Adobe’s website.
For more information, please visit: http://support.apple.com/kb/HT5271.
Apple released similar tools for Lion and Snow Leopard earlier in the year, and Monday’s updates merely bring the older version of OS X/Mac OS X in line with the newer versions. On My 9th, Apple released Safari 5.1.7, which also disabled out of date versions of Flash on Lion and Snow Leopard.