Join Entrepreneur+ for $5
Learn More

A Facebook Engineer Stalked Female Users. A Dentist's Receptionist Stole Patients' Identities. Here's How to Prevent These Things From Happening at Your Company.

Malicious insiders are the most dangerous security risk of all.

Opinions expressed by Entrepreneur contributors are their own.

A major risk to businesses is one that they often overlook -- rogue employees, also known as the "insider threat."

Focus Stock Fotografico | Getty Images

Related: No One Is Safe From the Data Breach Epidemic (Infographic)

While many companies today are devoting more resources to preventing hackers from stealing sensitive information, rogue employees can pose a far more serious risk because they have inside access to company secrets, clients and technologies, and they are often not sufficiently monitored. According to the Ponemon Institute, the cost of an insider-related incident is actually higher than a data breach caused by an outside hacker - $4.3 million per incident versus $3.62 million, respectively, and these costs could exceed $8 million over a 12-month period.

Insider threats are also on the rise. A 2018 report by the Ponemon Institute found that malicious insider incidents have grown by 56 percent since 2016.

A quick scan of the news on any given week will show how prevalent these cases are. For instance, in a recent case at Facebook, a security engineer was accused of abusing his privileged access to stalk women online. In January, a Chinese company was found guilty of using an AMSC employee to steal $800 million worth of intellectual property from that company. In April, a former Manhattan dental office receptionist was convicted of stealing the identities of over 650 patients. And the list goes on and on.

Related: Passwords Are Scarily Insecure. Here Are a Few Safer Alternatives.

Yet, in spite of the risks, many companies remain unprepared. Nearly one-third of companies admit they have no ability to prevent or deter an insider attack, and only 9 percent consider their insider prevention measures to be effective, according to a 2015 study by the SANS Institute.

Preventing this type of abuse isn't easy, but it can be done.

Here are four ways to manage the risk posed by trusted insiders.

Access controls

The key to reducing a company's exposure to insider threats is by creating strong "access controls" that prevent how much data a single employee is able to freely access in the first place.

No single employee should have unfettered access to all of the company's secrets -- rather, sensitive data should be siloed, and employee access should be decided on a case by case basis, determined by the employee's need to access such data in order to fulfill her duties. For example, a sales manager does not need access to the company's intellectual property, and an IT administrator does not need access to the company's client roster. The separate roles within a company should also be separated by the level of data access they have.

Related: Making Your Data Unreadable to Whoever Steals It Might Be the Only Way to Keep It Safe

Technical controls

In addition to establishing policy controls on data access, a company should also have in place strong technical controls that prevent over-access or abuse by insiders.

These controls should include: encrypting highly sensitive data, so that only specific people can access it; blocking or restricting certain types of tools and websites from employee devices, such as Tor, file transfer protocol (FTP) services, etc.; restricting the use of remote logins to the company's network; resetting passwords immediately for any terminated employee; and requiring regular password resets for all employee accounts in order to reduce the likelihood of learned or shared passwords.

Mobile device management

This is another crucial step, particularly in today's highly mobile and bring-your-own-device business world. A mobile device management (MDM) service enables a company to monitor the content on both company-owned and personally owned devices, as well as to containerize company data and allow for remote wiping if needed.

Related: Why This Cybersecurity Expert Wants You to Rethink What You Keep Secret


There are many different tools available for keeping an eye on employees, ranging from all-inclusive Big Brother-style technologies that monitor all employee activity on devices (such as email, social media, web browsing, etc.) to more focused tools like exfiltration monitoring, which only look for files being transmitted from the company network to a remote IP address.

However, it's important for companies to not be too heavy-handed with employee monitoring, or it could backfire. If employees feel they aren't trusted or valued by the company, they could act out -- the exact thing the company is trying to avoid in the first place.

It is best to take a more moderate approach with monitoring, by focusing on what really matters. Exfiltration monitoring, file access monitoring (who is accessing important files, and when and where) and email monitoring are three good steps to take.

Related: What You Need to Know About Multifactor Authentication

While there is no way to completely eliminate the insider threat, by taking a few key steps, companies can drastically lower their risk and keep employees in check. For more on this issue, see the FBI's tip sheet on averting the insider threat.

Entrepreneur Editors' Picks