A German engineering company says it has fixed loopholes in its software that allowed the notorious Stuxnet malware to attack industrial plants and factories. The highest-profile target of Stuxnet was Iran\'s nuclear enrichment efforts, as the computer worm targeted devices controlling the delicate industrial processes involved. Engineering giant Siemens said Stuxnet exploited loopholes in the software that oversees the running of its programmable logic controllers that are meant to automate a production process. Siemens has issued advisories saying it has updated the Simatic code in the controllers to remove the loopholes, the BBC reported Tuesday. While there is ongoing debate as to who created Stuxnet, security researchers say it is so complex and tightly targeted only a nation would be able to marshal the resources to put it together. Many have pointed the finger at the United States and Israel, speculating the aim of Stuxnet was to slow down and disrupt Iran\'s nuclear production capabilities.