SanDisk has stepped up its efforts to convince corporates that USB sticks are a secure medium, adding built-in antivirus capability to its latest Cruzer drive.

Any files copied or saved to the latest Cruzer Enterprise will automatically be scanned by a McAfee heuristics and antivirus engine that loads every time the drive is used. If it detects infected files being copied from a PC, all further transfers will be disallowed form that machine, stopping their spread.

The feature addresses the oft-made accusation that USB sticks can act like the floppy drives of old, allowing malware to circumvent firewalls and gateways if an infected drive is brought back into the network.

SanDisk itself warned of the related issue of data loss from USB drives issue earlier this year in a study of user behavior. All Cruzer Enterprise drives already feature enforced 256-bit AES encryption, which can be managed with a central server for smooth key recovery and policy-based security.

Anti-malware is unheard of, however, and part of the reason is that it adds complexity and expense. The drive has to carry around with it a database of malware signatures and rules, both of which need to be regularly updated to remain a viable means of defense. The licensing of McAfee's portable antivirus engine inevitably adds to the price.

"Cruzer Enterprise is an ideal solution for the mobile workforce and for IT departments concerned with data security, because it allows employees to have access to data everywhere and yet be fully protected," said SanDisk's Roy Ramati. "Adding McAfee's technology to our security solutions for the enterprise enables our customers to extend their security perimeter to mobile storage."

At the time of going to press, SanDisk had yet to confirm the nature of the signature updating process, but it would presumably be similar to that used by McAfee's existing USB-based scanning product, VirusScan USB, which works using the U3 software environment. Updates to this are made each time the device is plugged in on the U3 is up and running, and don't interfere with any security programs already running on the host PC.

McAfee's success with this product is unknown though the U3 environment has struggled since its inception in 2005 to achieve popularity. It is possible that the advent of antivirus security on mainstream USB drives could give it a new lease of life if it catches on more widely.