If the host residing on your internal network becomes compromised, it can undermine your firewall and open the possibility of attacks on other internal hosts. Keep in mind that any commercial OS, including Unix, will include default settings that are not optimized for security. While it may be tricky to lock them all down, success will make it easier to keep abreast of new OS releases. If you're new to OS administration, don't expose the OS to the Internet until you're confident of your level of protection. If you can choose the OS for a specific application, give some thought to in-house expertise regarding the OS's security.
Vendors address newly discovered vulnerabilities by continuously issuing patches.
Naturally, you'll want to ensure that any OS you install contains the latest patches for that particular version. And Network Computing will soon offer its own security alerting service, Network Computing Security Express. If the application doesn't limit the input, it will be written into system memory, and if the right string of characters is written into system memory, it will be interpreted as executable code. The kernel-bashing program causes the called program to abort while it is running, exiting into the root shell and giving root access to the user. This type of attack can only occur if a user is logged into the system.