Windows Malicious Software Removal Tool Observations

Microsoft released a pdf file called MSRT - Progress Made Lessons Learned yesterday which provides an analysis of the data that the program reported when scanning computers. The tool itself was executed more than 2.7 billion times on at least 270 million unique computers since January 13th, 2005. The tool has removed more than 16 million instances of malicious software which means that on average every 311th computer was infected.

Backdoors and Trojans were found on 3,5 million unique computers which means that a backdoor trojan was active in 62% of the infected computers. Rootkits have been found in 14% of all infected computers with 6% identified as the Sony BMG Rootkit. About 80% of the computers were newly infected ones while 20% were computers that had been infected before.

I think Microsoft presents some interesting stats. The tool itself scans for only a fraction of circulating malware and was still able to clean a large number of scanned computers. It´s alarming that 20% of the computers were infected more than once which seems to suggest that their owners did not learn from past errors.

Microsoft should think about an education program released with the software removal tool educating the users of infected pcs what went wrong and how they could secure their computers to prevent an infection in the future.