Appendix B. Linux Security Index—Past Linux Security Issues

Security is an ongoing process, not an end. An application that is deemed secure today may later prove to be vulnerable. For this reason, you should always keep up on recent security advisories and install recent updates. (The Glossary provides many resources to do just that.)

Some folks advise against installing the latest updates, arguing that newer software is bound to contain bugs unknown and undiscovered. To some extent, that's true. However, updates also solve older, better-known holes. This trade-off is definitely worth it. (In software that has no well-known holes, hackers and crackers must work to find an in; in software that has not been updated, attackers already have an in.)