Protecting your System - Keeping the 'Bad Guys' out
by Richard J. Silvers
Website: http://one.zer0x.net/~rjsilvers

No matter what anybody tells you, your computer simply isn't secure. By their very nature, computers are vulnerable. There will always be programming flaws, vulnerabilities, and misconfigured applications that can lead to your computer and the data within it being compromised.

There are literally dozens of software solutions that will lead you to believe that they can secure your system (usually for a small fee.) The first thing you must realize is that a software solution can never cover all your security bases; there will always be hardware vulnerabilities that they cannot address. The second thing is that these applications are vulnerable to the same types of exploits that plague the big application developers such as Microsoft.

With the explosion of always-on internet connections such as DSL and cable modems, your computer can be vulnerable to security exploits 24 hours a day, 7 days a week. Coupled with this, high-speed data transfers allow your computer to become compromised faster than ever.

The most basic, and useful, tool to protecting your PC is understanding the ways your computer can be exploited and knowing the steps you can perform to minimize these risks. You must be proactive when dealing with computer security. While there is no 100% guaranteed security solution, you should try to make it as difficult as possible to compromise your system. Force the bad guys to break in, rather than sneak in.

Security Risks

Viruses - Viruses live up to their namesake by being able to self-replicate their code to infect other programs or computers. The first computer virus was made in 1975 as a way of distributing a computer game, oddly enough. Since then, tens of thousands of these malicious programs have been unleashed on the internet.

Viruses have typically been distributed as an infected executable file (.exe or .com file). These files typically had to be downloaded or run from an infected disk. But more recently, exploits in certain programs have opened a wide range of new avenues for virus propagation. Your computer can now be infected by a virus just by being connected to the internet.

Spyware - Spyware is a relatively new plague to inflict the internet. While not as destructive as viruses, spyware is extremely annoying. It is most often recognized by unwanted pop-up windows, unsolicited advertisements, and sluggish system performance.

Spyware can be bundled with programs you install, it can be downloaded by accident from web pages, or can be maliciously installed on your system via software exploits. Spyware will then begin to track your computer behavior and collect data about you to send over the internet to one of their servers.

Web Cookies - Web cookies are small files placed in your internet cache that allows a web site to store data specific to a given user. Frequently, these are used by commercial web sites to store log-in information between sessions. However, internet advertising resellers are using the same technique as a consumer profiling tool with focused advertising being pushed your way by their sponsors.

Defending your System

Keep your OS updated - One of the major steps you can perform to keep your system secure is to keep it regularly updated. If you are using Windows 98 through Windows XP, Microsoft offers Microsoft's Windows Update as a way to download and install all the latest patches. Virtually every desktop OS has a similar mechanism to supply updates and most can be automated. If the process can't be automated, check for updates at least once a month if not weekly.

Install (and use!) Antivirus Software - Antivirus software is essential in keeping your computer secure. Most antivirus packages available today are inexpensive or free. A few of the packages I recommend for home systems are Trend Micro PC-Cillin, AVG Anti-Virus, and Panda Antivirus. To protect your company from threats, you really can't beat Symantec Anti-Virus Corporate for ease of distribution and updating.

Antivirus programs require that you install updates to detect the latest viruses. It makes no sense to install an antivirus solution and not keep it up to date. It's one of the most important things you can do to enhance your security.

Install a Personal Firewall - Firewalls can help keep intruders out by blocking access to your ports on the internet. Often, they make your computer completely stealth to potential attackers. If you are using Windows XP updated with Service Pack 2, you already have a decent firewall on your computer. For a more secure and configurable solution, try Zonelabs Personal Firewall. However, there are a few problems with both previously mentioned products. They must be running on your computer (consuming valuable resources) to be effective and they also can be vulnerable to software exploits like every other application. For increased security, consider purchasing a hardware firewall product.

Conclusion

These are your first lines of defense in keeping your computer and data safe. There will always be vulnerabilities: both with hardware and software, and social engineering tactics. Following these steps will at least get you started in the right direction and prevent all but the most dedicated of intruders from getting into your system.