2.2.3 Old Software Versions (#3)
Linux is not perfect. There are new vulnerabilities being found monthly.3 Do not despair, though. The speed with which problems are found and fixed in Linux is the fastest on the planet. Your challenge as an administrator is to keep up with the changes.
Each distribution has a mailing list that you can (and should) subscribe to, where security bulletins are issued, and an FTP or Web site at which the fix will be available. Also, there are the independent security mailing lists, such as Bugtraq and X-Force's Alert, that are excellent. Get yourself tapped into those mailing lists.
Subscribe to Bugtraq by sending e-mail to LISTSERV@LISTS.NETSPACE.ORG with contents of
Subscribe to X-Force's Alert by sending e-mail to firstname.lastname@example.org with contents of
subscribe alert email@example.com.
Other good sources of Linux security information are:
They are distribution-neutral and carry all the major distributions' security advisories. There is much more information on Web resources in Appendix A.
One of the beauties of Linux is that when a fix is issued, it is very quick to install, and unless it is in the kernel, your downtime for that service is on the order of seconds or minutes. Rarely, if ever, is a reboot necessary.