What’s at the top of the list of IT security worries at U.S. companies?

That would be outbound e-mail.

In its fifth-annual study of outbound e-mail and data loss prevention issues (read it here), Proofpoint, Inc. learned that large enterprises continue see risk from—and take action against—information leaks over outbound e-mail. They’re also closely monitoring newer communications media like blogs, message boards, media-sharing sites and mobile devices.

Outbound e-mail remains a key source of risk for U.S. enterprises. A record 44% of surveyed companies reported investigating an e-mail leak of confidential information in the past 12 months.

And 41% of the largest companies surveyed (those with 20,000 or more employees) say they employ folks to read or in some way assess the contents of outbound e-mail. 22% of these companies said they have workers who are used primarily or exclusively for this purpose. Other key findings in the survey include:

• 40% of companies surveyed investigated an e-mail-based violation of privacy or data protection regulations in the past 12 months.
• 26% of companies surveyed terminated an employee for violating e-mail policies in the last 12 months.
• 23% of U.S. companies surveyed said their business was impacted by the exposure of sensitive or embarrassing information in the last 12 months.
• 34% of the largest companies (20,000 employees or more) reported that employee e-mail was subpoenaed in the last 12 months.

E-mail isn’t the only source of risk for information leaks, however.

Survey respondents saw significant risk in employee use of blogs, message boards and media sharing sites (i.e., YouTube), as well as mobile devices. Additional findings:

• 27% of companies surveyed investigated exposure of confidential, sensitive or private information from lost or stolen mobile devices in the past 12 months.
• 11% of U.S. companies surveyed disciplined employees for improper use of blogs/message boards in the past 12 months.
• 13% of surveyed companies disciplined employees for social network violations and 14% for improper use of media sharing sites in the past 12 months.
• 14% of publicly traded companies surveyed had investigated the exposure of material financial information (such as unannounced financial results) on blogs or message board postings in the last 12 months.

Tags: blogs, e-mail, leaks, security, social networking