The Real Danger Comes from Within

When most people picture a cyberattack, they imagine someone on the outside trying to break in.

But what happens when the person already has access?

Employees, contractors, vendors, and other trusted users need access to company systems and information to do their jobs. That access is necessary, but it can also create cybersecurity risk when an account is compromised, someone makes an honest mistake, permissions are too broad, or access falls into the wrong hands.

This is where insider threats come into the picture.

And contrary to what the name might suggest, an insider threat doesn’t automatically mean a disgruntled employee intentionally trying to hurt the company. CISA defines an insider threat as the potential for someone with authorized access or knowledge to harm an organization, whether through malicious, complacent, or unintentional actions.

Understanding that distinction is one of the first steps toward managing insider risk effectively.

What Is an Insider Threat?

An insider is anyone who has or previously had authorized access to your organization’s resources. That can include employees, contractors, vendors, partners, and others who have access to systems, facilities or sensitive information.

The risk comes from what happens to that access.

Consider a few everyday examples:

• An employee accidentally emails a confidential spreadsheet to the wrong person.
• Someone saves sensitive company information to an unauthorized personal cloud account.
• An employee’s Microsoft 365 credentials are stolen through phishing.
• A former employee’s account remains active after departure.
• A user downloads sensitive business information before leaving the company.
• An employee copies confidential company data into an unapproved AI platform.
• Someone with administrative privileges uses those permissions inappropriately.

These situations look very different, but they have something important in common: legitimate access becomes a potential pathway to sensitive information.

The Three Insider Threats Businesses Should Understand

1. The Negligent Insider

This is often the easiest type of insider risk to overlook because there may be no bad intention at all.

Someone clicks a phishing link. A sensitive attachment goes to the wrong recipient. An employee reuses a password. A laptop containing company data gets left somewhere it shouldn’t.

The employee isn’t trying to create a security incident. They’re simply human.

That is exactly why cybersecurity training should go beyond an annual compliance exercise. Employees need regular, practical guidance that helps them recognize the situations they actually encounter at work.

BEI’s existing cybersecurity materials take this approach by emphasizing recurring education, including quarterly, annual and short-form micro training rather than treating awareness as a one-time event.

2. The Compromised Insider

Sometimes the employee isn’t really the person behind the activity.

Imagine an attacker successfully steals an employee’s credentials through phishing. As far as your systems are concerned, the attacker may initially look like an authorized user.

They aren’t necessarily “breaking in” through the front door. They may be logging in with a real username and password.

This is one reason identity security deserves so much attention. Multi-factor authentication, strong password practices, conditional access, endpoint security and monitoring for unusual behavior all provide additional layers between stolen credentials and sensitive business information.

It also reinforces an important lesson: legitimate credentials do not automatically mean legitimate activity.

3. The Malicious Insider

This is the scenario most people associate with insider threats.

A disgruntled employee might deliberately steal customer records. Someone could copy intellectual property before accepting another job. A privileged administrator might intentionally misuse elevated system access.

Malicious insider incidents may be less common than some everyday security mistakes, but their impact can be substantial because the individual may already understand where important information resides and how the company’s systems operate.

The IBM 2025 Cost of a Data Breach Report highlights malicious insider activity among the range of threats contributing to modern breaches. IBM’s study examined 600 organizations affected by data breaches across 17 industries and 16 countries and regions.

Why Insider Threats Can Be Difficult to Detect

External attackers and insiders present fundamentally different challenges.

If someone repeatedly attempts to log into an account from an unusual location, the activity might immediately look suspicious.

But what if an authorized employee downloads 500 files?

Maybe they’re preparing information for an important presentation.

Or maybe they’re moving files somewhere they shouldn’t.

Or maybe their account has been compromised.

The activity itself doesn’t always reveal intent.

That’s why effective insider threat prevention requires context as well as technology. Businesses need visibility into access, permissions, devices and security events while maintaining reasonable policies that allow employees to get their work done.

According to CISA’s updated Insider Threat Mitigation Guide, organizations should take a structured approach that includes identifying insider risks, assessment, threat management and establishing or improving an insider threat mitigation program. The latest guidance also accounts for evolving workplace realities such as hybrid and remote work and AI.

Remote and Hybrid Work Have Changed the Equation

The traditional office security perimeter has changed considerably.

Today, company information may be accessed from:

• Home offices
• Airports and hotels
• Personal internet connections
• Mobile devices
• Cloud applications
• Microsoft 365
• SaaS platforms
• Third-party systems

This doesn’t mean remote work is inherently insecure. It simply means businesses must make security controls work wherever their employees work.

BEI’s own Insider Threats in a Remote Work World recommends combining appropriate access controls, identity and access management, employee education, risk monitoring and policies employees can realistically follow.

The goal isn’t to monitor every move employees make. It is to build sensible security guardrails around company information.

AI Is Creating Another Form of Insider Risk

There’s also a newer question businesses need to answer:

Where are employees putting company information when they use AI?

Generative AI has quickly become part of everyday business workflows. An employee might paste customer information, an internal financial report, proprietary code or meeting notes into an AI platform because they’re trying to work more efficiently.

Their intention may be completely harmless.

The data exposure may not be.

IBM’s research illustrates the challenge. Its 2025 breach research found that 63% of the breached organizations studied lacked AI governance policies, highlighting the gap between rapid AI adoption and formal oversight.

Businesses don’t necessarily need to prohibit AI. They need policies clearly explaining:

• Which AI tools employees may use
• What company data can and cannot be entered
• How customer and regulated information should be handled
• Whether AI-generated work needs review
• Who employees should ask when they’re uncertain

Good policy should make the secure choice easy to understand.

7 Ways to Reduce Insider Threats

Insider threat prevention shouldn’t rely on any single security tool. The strongest defense combines people, processes and technology.

1. Follow the Principle of Least Privilege

Employees should have access to the information and systems necessary for their role, but not everything in the organization.

Someone in marketing probably doesn’t need administrative access to financial systems. Likewise, an accounting employee may not need access to every technical platform.

Review permissions regularly, particularly when an employee changes roles.

2. Require Multi-Factor Authentication

Passwords can be stolen.

MFA adds another verification requirement, making a stolen password alone less useful to an attacker.

Pay particular attention to privileged and administrative accounts because compromising one can provide much broader access.

3. Make Cybersecurity Training Continuous

Don’t expect employees to remember everything from a one-hour training completed months ago.

Short, recurring training can reinforce behaviors such as:

• Recognizing phishing attempts
• Handling sensitive information
• Using MFA safely
• Reporting suspicious activity
• Protecting passwords
• Working securely outside the office
• Using AI responsibly

4. Review Access Regularly

Access tends to accumulate.

An employee changes departments but keeps permissions from the old role. A temporary project ends but shared-folder access remains. A contractor finishes an assignment but still has an active account.

Periodic access reviews help answer a simple question:

Does this person still need this access?

If the answer is no, remove it.

5. Build a Reliable Offboarding Process

Cybersecurity needs to be part of employee departures.

Depending on the person’s access and responsibilities, offboarding can include:

• Disabling company accounts
• Revoking active sessions
• Removing VPN and remote access
• Recovering laptops and mobile devices
• Changing shared credentials
• Transferring ownership of company files
• Reviewing administrative privileges
• Removing access to third-party applications

The process should involve both HR and IT so departures don’t leave forgotten digital access behind. Current CISA guidance specifically includes employee separation among the areas organizations should address in insider threat mitigation. [cisa.gov]

6. Protect Sensitive Information

Not all company data should receive the same treatment.

Identify where your most important information lives and who can access it. That may include:

• Customer information
• Protected health information
• Personally identifiable information
• Financial records
• Intellectual property
• Contracts
• Employee information
• Government or regulated data

From there, organizations can apply appropriate access restrictions, encryption, monitoring and retention policies based on the sensitivity of the information.

7. Give Employees a Simple Way to Report Problems

Employees are much more likely to report something quickly when they know what to do.

Someone who accidentally sends sensitive information to the wrong recipient shouldn’t spend an hour wondering whether they’ll get in trouble for reporting it.

Create a straightforward incident-reporting process and encourage employees to use it.

Speed matters. The sooner IT or security teams know about suspicious activity or an honest mistake, the sooner they can assess the situation and limit potential damage.

Insider Threat Prevention Is About Building Better Guardrails

An effective insider threat strategy isn’t built on the assumption that employees can’t be trusted.

It’s built on the reality that people make mistakes, accounts get compromised, responsibilities change and access can become outdated.

A well-designed cybersecurity program accounts for those realities.

Employees receive useful training. Access matches job responsibilities. MFA provides another layer of protection. Sensitive information receives stronger safeguards. Accounts are removed promptly when employees leave. And unusual activity can be investigated before it becomes a much larger problem.

That’s a much healthier approach than relying on employees to never make a mistake.

Don’t Wait for an Insider Incident to Find the Gaps

You don’t have to treat every employee like a security threat to take insider risk seriously.

Start with the basics: understand who has access to sensitive information, make sure permissions match business needs, strengthen account security, provide ongoing cybersecurity education and establish clear procedures for onboarding, role changes and departures.

From there, organizations can identify where stronger security controls or monitoring make sense.

BEI can help businesses take that practical approach, from cybersecurity risk assessments and security awareness training to identity, access and endpoint protections. These protections also align with BEI’s existing approach to insider risk, which emphasizes access controls, endpoint protection, employee training and risk assessments rather than fear-based monitoring.

Concerned about who has access to your company’s sensitive information, or whether your current security controls are enough? Contact BEI to discuss practical ways to strengthen your cybersecurity posture and reduce insider risk.