Security watchers have discovered a worm that targets drawings created in AutoCAD software for computer-aided design (CAD).

Tens of thousands of drawings have been swiped using the malware, which is likely to have been designed for industrial espionage, according to antivirus firm Eset. The worm, dubbed ACAD/Medre.A, steals files and sends them to email accounts located in China. ESET said it had worked with Chinese ISP Tencent, the Chinese National Computer Virus Emergency Response Center and Autodesk – the creator of AutoCAD – to stop the harvesting of drawings by blocking email accounts associated with relaying stolen data. Business users in Peru were the main victims of the attack.

"The high number of infections observed in Peru might also be explained by the fact that malware disguised as AutoCAD files may have been distributed to companies that were conducting business with public services in Peru," according to Eset. "This leads us to think organisations in this country might have been the primary target of the ACAD/Medre.A operators."

The malware has also cropped up elsewhere in Latin America but Peruvian users were the main target. The miscreants behind the attack were using internet resources in China as dropsites in a delivery chain but it doesn't necessarily follow that they were Chinese.

"After some configuration, ACAD/Medre.A sends opened AutoCAD drawings by email to a recipient with an email account at the Chinese 163.com internet provider," explained ESET Senior Research Fellow Righard Zwienenberg. "It will try to do this using 22 other accounts at 163.com and 21 accounts at qq.com, another Chinese internet provider.

"ACAD/Medre.A represents a serious case of industrial espionage. Every new design is sent automatically to the operator of this malware. Needless to say this can cost the legitimate owner of the intellectual property a lot of money as the cybercriminals have access to the designs even before they go into production," he added.

ESET has released a free stand-alone cleaner utility to aid in the clean-up of infected systems.

AutoCAD malware strains are rare but not unprecedented. For example an AutoCAD virus surfaced in 2009.

More details on the AutoCAD worm attack can be found in a blog post by Eset here. ®