While there are constantly new attacks circulating, some of the most popular methods are the older attacks that are well established. Many of these older attacks continue as they open up the PC’s security more extensively than some of the newer attacks that are difficult to exploit.  While the M86 report may not completely reflect the malware landscape, it still illustrates the value of staying up to date with all software installed (including all non-MS patches)

Which Old Vulnerabilities Are Still Exploiting Our PCs?
http://blogs.pcmag.com/securitywatch/2011/02/which_old_vulnerabilities_are.php

QUOTE: There have been many stories in the last few days reporting data released by M86 Labs which shows that the list of vulnerabilities being exploited by the “most observed threats” was dominated by those patched many years ago. The implication of the reports is that there are still a lot of people out there who haven’t patched their systems in years.

Top 5 Most Observed Vulnerabilities – January 2011
http://www.m86security.com/labs/malware-statistics.asp

QUOTE: Anonymized feedback from M86 filtering installations showed most observed threats were based on the following vulnerabilities:

Vulnerability / Year Disclosed / Year Patched
1. Microsoft Internet Explorer RDS ActiveX 2006 2006
2. Real Player IERPCtl Remote Code Execution 2007 2007
3. Office Web Components Active Script Execution 2002 2002
4. Microsoft Access Snapshot Viewer ActiveX Control 2008 2008
5. Microsoft Internet Explorer Deleted Object Event Handling 2010 2010