Apple has released security update 2007-009 which contains fixes for several key components of the Mac OS X operating system. The following downloads are now available:

2007-009 10.5.1 includes fixes for CF Network, Core Foundation, CUPS, Flash Player Plug-in, Launch Services, perl, python, Quick Look, ruby, Safari, Samba, Shockwave Plug-in and Spin Tracer.

2007-009 10.4.11 Universal and 10.4.11 PPC include fixes for Address Book, CUPS, ColorSync, Core Foundation, Desktop Services, Flash Player Plug-in, gnutar, iChat, IO Storage Family, Launch Services, Mail, perl, python, ruby, Samba, Safari, Shockwave Plug-in, SMB, Spotlight, tcpdump and XQuery

Several of these issues are rather serious, so we strongly advise installing these updates at your earliest convenience. You can read up on the individual CVE numbers and vulnerability descriptions here.