10.3% of Malware now delivered by USB storage

Back in the early days of computers when most people and businesses either did not have Internet access or just used dial-up Internet access sparingly, most viruses were designed to infect floppy disks to make their way around through the sharing of floppy disks.  For example, some viruses that time infected the floppy disk’s boot sector, as they took advantage of the fact that users often forget to eject their disk before booting the PC and most PCs were configured to try booting from floppy first by default.  Then when the Internet access became widespread, the majority of virus writers turned to using a combination of unpatched windows PCs, infected e-mail attachments, trojans and social engineering. 

Now with the growing popularity of removable storage again and most consumers assume that viruses come from infected e-mail attachments and dodgy websites, some have forgotten that removable storage can also carry viruses.  According to this EFYtimes report, ESET said that USB pen drives have started becoming a growing source of malware beginning last summer with viruses making use of the Autorun capability, a feature commonly used on CD/DVD-ROM titles to start the disc software upon loading the disc.  This method of distributing malware has grown to the point where the INF/Autorun generic identification for malware has remained the number one way of compromising PCs in March with USB distributable malware accounting for 10.3% of malware detected that month. 

Despite this growing use of using USB storage to distribute malware, some people believe they are safe from malware by either keeping a close eye on what e-mail attachments they open and what they access online or in certain cases keeping their work PC permanently offline.  Unfortunately, this certainly does not protect them from malware if they regularly use USB storage, particularly when this USB storage has been used on public PCs and those with permanently disconnected PCs also assuming they don’t need a virus checker.