A single group of hackers using spearphishing has stolen industrial drawings, contracts and more from at least 10 oil, gas and defense companies in Norway, according to a published report.
Targeted e-mails sent while the companies were engaged in negotiations for large contracts contained malware that enabled the attackers to steal then exfiltrate the information, according to a report by the BBC.
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Perhaps more firms were victimized, the Norwegian national security agency NSM says, but they haven't come forward, according to the BBC report.
User names, passwords, industrial drawings and contracts were among the data stolen, it says.
Based on code within the malware, methods used to target individual email accounts and how the data was extracted leads the NSM to think that one group perpetrated all the attacks, the BBC says.
The spearphishing was aimed at carefully chosen individuals and appeared to be legitimate, the report says.
This is the first time Norway has announced such a widespread espionage attack, but it wants the incidents to serve as warnings to others. The NSM is also encouraging other businesses that might have been targeted to come forward, the report says.
It is likely that many firms have been hit but don't know about it yet, NSM says.
The attacks were discovered by what NSM describes as vigilant users who reported them to IT staff within their companies. The companies then told NSM.