Macintosh OS X Security – Second Lesson – Chevell
MAC OS X The early adopters have been using OSX 10.0 for the better part of two weeks now. Early adopters, while not all the UNIX gurus and application developers Apple targeted the release for, are zealous, ambitious and daring- perhaps too much so.
As I stated in my previous Mac OS X Security overview, Mac OS X is a completely new operating system to most Mac users. Its UNIX under pinnings are foreign to the point-and-click community. The interface is certainly foreign to anyone but NeXT/OpenStep users and Mac OS X Server administrators. Even to this select group OSX has a large amount of new and changed schemes and strategies, making the conversion to the platform a bit daunting. And even to the UNIX users, Mac OS X is part alien with its revised directory structure and customized binaries.
With all the foreign elements of Mac OS X it is important to approach the system with a certain degree of caution. Gone are the days when a Mac user can install an application, restart and then worry about what it does, removing it quite easily from service if any issue is detected. Virus software, tossed in the bottom desk drawer, now requires a second thought. A whole new outlook on security is required at this point in order to maintain data integrity and personal safety.
The previous article described several methods, which can help maintain security in any computer system. These steps are absolutely imperative to security and, without them, any further steps to ensure safety will be fruitless. Practice these methods religiously and effectively cut 95% of all hack attempts, malicious vandalism or virus attacks.
Beyond these basic steps, users can take advanced steps to ensure security on their new system. The best tip here is not doing anything. When the OS shipped, Apple had security on the brain. The system state directly after installation is the most secure point in the system’s entire life cycle. It’s the moment user accounts are added, preferences set, and sharing methods are opened that the system becomes susceptible to attack or failure.
Of course the whole point of having the computer, and connecting it to the Internet, is to use it, customize it and to share it. But caution should be taken when making such modifications. When adding a user via the User preference panel, ensure that the password is and will remain secure. Do not give Administrator access to every account. In fact, most systems will only need a single administrator account, while the rest may safely remain users.
Adding customized applications to the system can sometimes open up communication ports on the machine. Unbenounced to the user, this new application might even allow communication two an from a system from a remote server, even without warning. A perfect example of this kind of software is the Software Updater. This application contacts Apple Computer on a daily or weekly basis and allows Apple to install items onto your system. I am not suggesting that you turn off Software Update or even worry about it, because if you can’t trust Apple, who can you trust? There are, however, several other types of applications that use Software Version Control to update software after communicating with a remote server, similar to the way the Software Updater does, but not from such a trustworthy source. If you find this option in a freshly installed application, it would be advisable to turn it off and use VersionTracker.com or similar resource to find the latest updates.
File and web sharing is a great way to get an instant Internet presence or connect to remote resources. It is also a great way to allow all sorts of malicious and maligned individuals access to personal data. There is always a new exploit found for this version of that software or a patch released to fix security issues in another. For this reason, use file and web sharing carefully. If the machine will not be used for remote Command Line Interface access, do not turn on the option for it in the Sharing preference panel. Also, not everyone needs a web site running from his or her daily workhorse. Most users have web server access via their Internet Service Provider and can simply leave the local web server off. FTP access is another oft not used feature that can most likely be turned off. File sharing with AppleShare of IP is probably adequate for most users.
Beyond not modifying the system from its install state, there are a few changes anyone can make to the system to help make it even more secure. SSH is Secure Shell and can be used to replace the telnet access provided with the operating system. Apple actually planned on bundling this security package with the system but licensing issues delayed it. Look for a patch from Apple to enable this option. Until then, OpenSSH is available on the web at Mac OS X.org and other related sites.
Keeping the system updated with the latest patches and software versions is also a great way to stay secure. As exploits are found in a particular software package, a company will release a patch or revision that will help close the hole. Apple will probably assist Mac OS X users with this task better then most other UNIX distributions but this remains to be seen. It might be required that the user be aware of these issues. SecureMac.com is a great place to stay up to date concerning these matters.
File permissions are a particularly sensitive area with regards to security. In its basic state, file permissions are of no consequence. When sharing methods are opened, however, these same permissions become a very large part of system security. It is not easy to modify the file permissions from the Graphical User Interface in Mac OS X but anyone who decides to dive into the CLI should take special care not to create any security holes when issuing commands via the command line. Information about file permissions and the CLI in general may be found in Mac OS X.org’s CLI Tutorials.
The key to secure commuting in the Mac OS X world is to be conscious of the environment, to stay up to date and to cautious of any changes made. Coupled with the basic steps for computer security outlined in part one of this article, these methods will help ensure a successful, safe and secure Mac OS X experience.