When an employee turns on his own company, the results -- damaged networks, data theft and even work stoppage -- could be devastating.
It could rock the company even more than an outside attack because the insider knows where sensitive data is kept, what the passwords are and exactly how to hurt the company the most.
That's the driving force behind the work that Daphne Yao, associate professor of computer science at Virginia Tech, is doing on cybersecurity.
Yao, who received an NSF Career award for her human-behavior inspired malware detection work, is developing algorithms that will alert companies when an employee might be acting maliciously on their network.
And the Army Research Office has awarded her $150,000 to continue her research into finding new ways to detect anomalies caused by system compromises and malicious insiders.
"The challenge is to understand the intention of the user and what the user is trying to do," Yao said. "Most are doing legitimate work and they're working their own project and minding their own business. You need a detection system that can guess what the user is trying to do."
The crux of Yao's work is to figure out which employees are simply downloading sensitive files or logging onto the network in the middle of the night because they're trying to get their work done and which employees may be doing the same things because they're trying to sell proprietary information or crash the network.
According to a 2012 Symantec report, 60% of companies said they had experienced attacks on their systems to steal proprietary information. The most frequent perpetrators were current or former employees or partners in trusted relationships.
In 1996, for instance, a network administrator at Omega Engineering Inc. planted a software time bomb that eradicated all the programs that ran the company's manufacturing operations at its Bridgeport, N.J. plant.
The trusted IT administrator, Tim Lloyd, effectively stopped the manufacturing company from being able to manufacture, causing the company $12 million in damages and its footing in the high-tech instrument and measurement market. Eighty workers lost their jobs as a result.
Lloyd was tried and convicted of computer sabotage in federal court.
More recently, in 2013 Edward Snowden leaked classified documents about global surveillance programs that he acquired while working as an NSA contractor.
The same year, Pfc. Bradley Manning, an Army intelligence analyst, was sentenced to 35 years for leaking the largest cache of classified documents in U.S. history.
These are the kinds of insider attacks Yao is working to stop.
The Army Research Office did not respond to a request for comment, but Dan Olds, an analyst with The Gabriel Consulting Group, said he's not surprised that the military is supporting research into detecting insider threats.
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