Some years ago, a small manufacturing firm was hijacked by its IT employees. They didn’t use any weapons, but they did commit murder: They killed the business.

Unfortunately, they were aided and abetted by the company’s own lax security policies. The firm had ignored the best practice of segregating duties: The IT employees who developed the core manufacturing software also were tasked with administering the system, supporting the end users and managing the backup process. When business conditions required the company to reorganize its IT staff, some of the employees who were to be laid off took revenge by sabotaging the mission-critical application. They erased audit trails, reassigned user rights, and even destroyed the backup tapes. The manufacturer never recovered from the assault.

That’s an extreme example of the havoc supposedly “trusted” insiders can wreak upon a company. Yet it’s not an isolated instance. Most privileged users have earned their organizations’ trust, but a single rogue employee can do great damage, disrupting or destroying systems or stealing corporate data. Even if these acts don’t leave a company in ruins, they may expose a business to heavy financial losses, fines for compliance violations, or negative publicity. 

Many organizations have yet to pay close attention to combating this threat. Companies in recent years have focused on the external threats, from hackers to phishers, which the media has so well covered. Yet privileged users within organizations can represent an even more significant risk. Their credentials often supply them with the “keys to the kingdom” that enable them to access and view data that they should not, and access and manage IT systems in a manner that could damage operations. Sometimes, the damage is the result of an accidental error, but it’s equally likely that malicious intent is behind the disruption.

Some startling facts about the risks posed by insiders are revealed in The Insider Threat Study: Computer System Sabotage in Critical Infrastructure Sectors. The May 2005 report, published by the U.S. Secret Service National Threat Assessment Center and the Carnegie Mellon Software Engineering Institute’s CERT program, focused on nearly 50 cases of insider sabotage carried out between 1996 and 2002. It found that 86% of insiders engaged in sabotage were employed in technical positions, the majority as system administrators, Most of them had privileged access to systems when hired, though less than half had authorized access at the time of the incident. Fifty-seven percent of insiders exploited systemic vulnerabilities in applications, processes or procedures, or a combination of these. In 81% of the affected organizations, insider activities resulted in financial losses—in at least one case, amounting to tens of millions of dollars. Three-quarters of the affected organizations suffered negative impacts to business operations, ranging from deleted sales records to the destruction of proprietary software, and nearly 30% experienced damage to their reputations.