Insider Security Threats: Real Cases, Missed Signs, and Hard Lessons

By now, you’ve heard me talk about insider threats – the types, the red flags, and growing risk.  But theory only gets us so far.

This is Part 4 of our Insider Threat series, and today we’re digging into real-world case studies that show what happens when the warning signs are missed – or worse, ignored.

These are public, verifiable incidents. And they’re exactly why organizations need smarter, intelligence-driven approaches to managing internal risk and enhancing their security.

Insider Threat Case #1: Anthony Levandowski & The Self-Driving Code He Took to Uber

What Happened:

Anthony Levandowski, a lead engineer at Google’s self-driving car division (Waymo), downloaded 14,000 confidential files before resigning and forming a competing startup – later acquired by Uber.  He was convicted in 2020 of trade secret theft and sentenced to 18 months in prison.

What Was Missed:

• File download spikes during resignation period.
• Requests for data outside his typical role.
• A hasty transition to a direct competitor in the same space.

Protective Intelligence Lesson:

This wasn’t a technical failure – it was a visibility failure. Corporate security teams must integrate insider threat detection with role-based monitoring and behavioral context.  When high-level talent gives notice, especially in high-risk departments like research & development, it should automatically trigger a risk review.

Insider Threat Case #2: The Twitter Social-Engineering Hack

What Happened:

In July 2020, hackers used phone-based social engineering to gain access to Twitter’s internal admin tools.  They compromised dozens of verified accounts, including Barack Obama, Elon Musk, and Joe Biden, then launched a Bitcoin scam netting over $100,000 USD.

What Was Missed:

• No multi-layered verification protocols for sensitive internal tools.
• Lack of role-based access limits.
• Over-trusting internal helpdesk procedures.

Protective Intelligence Lesson:

This was a classic case of human exploitation over system exploitation.  Insider threat programs that rely solely on technical security controls will fail. You need protective intelligence practices that blend training, behavioral analytics, and adversarial thinking. It is important to recognize that attackers aren’t just hacking your code, they’re hacking your people.

Insider Threat Case #3: The HR Ghost Employee Payroll Fraud (China, 2025)

What Happened:

An HR manager at a Shanghai tech firm created 22 fake employee records and routed payroll funds to herself over eight years, stealing nearly $2.2 million.  She was finally exposed when a co-worker flagged an employee with oddly “perfect” attendance.

What Was Missed:

• No vendor or payroll validation for small changes.
• Unchecked administrative privileges in HR systems.
• Minimal behavioral oversight in non-technical departments.

Protective Intelligence Lesson:

This case highlights a major blind spot: insider security risk isn’t just a cyber problem.  Your threat intelligence strategy needs to include HR, finance, and procurement – departments often excluded from security conversations but just as vulnerable to fraud and manipulation.

What These Insider Threat Cases Have in Common

Each of these incidents featured clear red flags:

• Behavioral shifts.
• Access misuse.
• Oversight failures.
• Siloed departments.

None of them were caught early – not because the signs weren’t there, but because no one was empowered to connect the dots.

At Convoy Group, we help organizations build that capability.  We don’t just write policies, we build protective intelligence programs that integrate security, HR, IT, and leadership so you can detect threats long before they become breaches.

Coming Up in Part 5 of the Insider Threat Series:

Next, we’ll explore how insider threats evolve in remote and hybrid work environments, and what needs to change when your perimeter is everywhere.

Want a second set of eyes on your insider risk posture?

Let’s talk: https://www.linkedin.com/in/christopherklossner/