Apple released two security updates for Mac OS X 10.5 Leopard.
The first is the Flashback Removal Security Update, which Apple describes as follows:
This update runs a malware removal tool that will remove the most common variants of the Flashback malware. If the Flashback malware is found, it presents a dialog notifying the user that malware was removed. There is no indication to the user if malware is not found.
The second is Leopard Security Update 2012-003, which performs an action that was in the latest update for the Safari web browser
This update disables Adobe Flash Player if it is older than 10.1.102.64 by moving its files to a new directory. This update presents the option to install an updated version of Flash Player from the Adobe website.
Download links and details are available at Flashback Removal Security Update and Leopard Security Update 2012-003 pages on under Apple's Support section, or users can get the update through Software Update directly on their Mac.
Mac OS X 10.5.8 is the last operating system that supports PowerPC processor based Mac.
UserAgent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_7_4) AppleWebKit/534.57.2 (KHTML, like Gecko) Version/5.1.7 Safari/534.57.2

