According to the SANS Institute, a prominent computer security company, it's your applications, not your operating system, that's probably putting you and your PC into the most danger from being attacked.
In its latest report, The Top Cyber Security Risks, based on data from over 9-million systems protected by TippingPoint intrusion prevention system, its your unpatched PC software that's most likely to give your computer a bad case of malware. The biggest targets aren't, as you might think, Web browsers or e-mail clients that work directly with the Internet. No, it's the applications like Adobe Flash and PDF Reader, Apple QuickTime, and Microsoft Office, that your Web browser or e-mail client call on to read or play media from the Web that's currently the real problem.
Here, says SANS writes, is how it works: "Waves of targeted email attacks, often called spear phishing [E-mail messages that look like they're real message from a trusted sender], are exploiting client-side vulnerabilities in commonly used programs. ... This is currently the primary initial infection vector used to compromise computers that have Internet access. Those same client-side vulnerabilities are exploited by attackers when users visit infected Web sites. Because the visitors feel safe downloading documents from the trusted sites, they are easily fooled into opening documents and music and video that exploit client-side vulnerabilities. Some exploits do not even require the user to open documents. Simply accessing an infected website is all that is needed to compromise the client software."
As usual, while the unpatched applications are the immediate problem, this is more of a Windows problem than it is for any other operating system. On Windows, it's simply much easier for an application that's been fed an infected file to spread the malware of the day to the rest of the PC.
That said, if you can stop the bug from hitting in the first place, whether you're running Windows, a Mac or Linux won't matter. The problem, as SANS points out is that even "On average, major organizations take at least twice as long to patch client-side vulnerabilities as they take to patch operating system vulnerabilities. In other words the highest priority risk is getting less attention than the lower priority risk."
In part that's because Microsoft, like everyone else, makes it easier to patch the operating system than the applications. That means that you need to stand up and make sure your applications are patched. You can't depend on the fix being pushed to you in a timely manner.
You used to be able to keep Microsoft Office up to speed by using Microsoft Office Update, but Microsoft turned that service off on August 1st 2009. Now, the easy way to update Office is to use Microsoft Update. In a blast from its "Allow no one but Microsoft true fans past," you can't use this site with Firefox or Chrome, you have to use Internet Explorer 5 or higher.
Using Vista? In that case, to enable Office updates, click the "Get updates for more products" link in the Windows Update dialog and follow Internet Explorer's in-browser instructions.
If you'd rather not use IE, you can still get the updates by going to the Windows Control Panel. If you're using the Classic view Click System, and then click the Automatic Updates tab. Like the Category view? Then, click Performance and Maintenance, hit System, and then click the Automatic Updates tab.
For Adobe programs, check out the Adobe Product Update page on a regular basis. Officially, Adobe has a quarterly patch schedule, but they update their programs, especially Adobe Flash), more often than that.
Firefox Flash users get a break here. Starting with the newest Firefox 3.5.3 and 3.0.14, Firefox automatically checks to see if you have the most up-to-date Flash software. Why did Mozilla choose to support another company's product? Well as SANS would agree, Mozilla spokesperson Johnathan Nightingale, observed that Flash Player is both very popular and "some studies have shown that as many as 80% of users currently have an out of date version."
Finally, to keep Apple QuickTime up to date, you should manually run the Apple Software Update program. By default, this program runs once a week. That's not often enough. You can set it to update more often or run it manually. Personally, mine is set to daily, as are my other Window update programs.
Of course other programs are problems too, and each and every one has its own way of being updated. Still, if you keep the programs above, and your Web browser and e-mail clients updated, you'll be a lot safer than you were.
It may be a nuisance to run multiple update programs, but as SANS has shown, the alternative is to leave your computer open to attack. And, since today alone, I've encountered a spear-phishing attack on Twitter and a Web site with a fake anti-virus message, the sooner you saddle up and start updating your programs, the better.