Bitglass, the Total Data Protection Company, has today released findings from a survey of 129 Black Hat conference attendees looking at the biggest data blind spots for corporate data.

It found that the top five data blind spots are unmanaged devices (61%), not-up-to-date systems (55%), mobile devices (36%), data at rest in the cloud (26%) and traditional on-premises security (21%).

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Regarding BYOD, businesses must make sure that employees can access the data they need to do their jobs, but it’s essential that the use of BYOD and company-managed mobile devices doesn’t negatively impact the security of that data.

Password protected documents (33%) were ranked as the least effective security measure, followed by facial recognition (19%) and access controls (16%).

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The survey also found that almost 60% of respondents ranked phishing as the number one method of data exfiltration, followed by malware (26%), while more than three quarters (83%) of respondents believed that hackers are motivated by the monetary value of data, with ego and entertainment-value playing only a small role.

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Commenting on the results, Rich Campagna, CEO at Bitglass, said: “Corporate security efforts are struggling to keep up with the proliferation of BYOD. Enterprises must ensure that employees can securely access data from any device, including unmanaged mobile devices. Controlling data, its location, and access to that data are critical capabilities to prevent data leakage and hacking.”

“The fact that phishing was ranked as the number one method of data exfiltration is particularly worrying given the challenges around securing BYOD. With little visibility into unmanaged devices, companies can struggle to identify and respond to phishing and malware.”