Apple has released the Security Update 2009-001 for Mac OS X today which improves the security of Mac OS X and recommended for all users.
The security update fixes the following:
- Safari RSS vulnerability
- Denial of service vulnerability in AFP server
- A flaw in CoreText
- A security flaw in Folder Manager that allows other local users access to a user's Downloads folder and other vulnerabilities.
The security update is available for Leopard, Leopard Server, Tiger for Intel Macs, Tiger for PowerPC-based Macs, Tiger Server for PowerPC-based Macs and Server Universal.
Two Java updates are also available which addresses security and compatibility issues and are compatible with both Intel and PowerPC-based Macs & applies to Mac OS X 10.5.6 or later versions.
More information about the update can be obtained here