The Insider Threat Risk Scaling Tech & Defence Companies Can’t Afford to Ignore

In fast-growth tech and defence companies, 60–70% of data breaches are caused by insiders not attackers. The most dangerous security gaps aren’t found in codebases or firewalls, but in your joiners, movers, leavers, and culture.

Not because your people are bad hires, but because growth creates gaps.

• Rapid hiring

• Expanding system access

• Sensitive IP

• Security clearance pressures

• Remote teams

• Investors asking governance questions

• Defence contracts requiring strict compliance

When scaling happens fast, integration often lags behind, and that right there is where insider threat risk quietly builds.

Behavioural changes go unnoticed in busy, scaling teams. Poor quality or rushed onboarding leads to values drift. Rapid promotions without vetting or behaviour review, can lead to an increased volume of employee relations issues.

Scaling also increases:

• Conflicts

• Burnout

• Complaints

• Performance struggles

• Misaligned expectations

Each of these is a behavioural precursor to insider risk.

But with HR overwhelmed, or not invested in, issues become transactional instead of investigative.

Cultural fracturing between old and new teams, underdeveloped middle management, Psychological safety drops as pressure increases.

In Tech & Defence, Access Is Power. In scaling tech companies:

• Engineers hold core IP

• Product teams access sensitive customer data

• DevOps teams hold production keys

• Contractors often have system-level permissions

In defence and security-adjacent organisations:

• Vetting levels matter

• Clearance status changes matter

• Data classification matters

• Reputational damage is catastrophic

Now layer in rapid growth, which includes new joiners, internal promotions, emergency hires, consultants, project-based contractors the list goes on!

Without tight HR–Security collaboration, access grows faster than oversight.

That’s not me being dramatic it simply is dangerous.

That’s what I truly believe HR and Security Must Operate as One System

Security understands:

• Clearance requirements

• Physical and digital access control

• Information assurance

• Regulatory exposure

HR understands:

• Behavioural shifts

• Engagement patterns

• Performance concerns

• Grievance processes

• Organisational culture

Insider threat often shows up as:

• Disengagement before data misuse

• Conflict before escalation

• Poor exits before IP loss

• Burnout before policy breaches

If we in HR see behaviour but, Security doesn’t see risk context, you have a blind spot.

If Security sees anomalies but HR doesn’t see behavioural context, you have another blind spot. Scaling businesses cannot afford blind spots, especially in defence or tech.

Where Scaling Organisations Get Caught Out

In fast-growth tech and defence environments, we often see:

• Vetting not reviewed when roles evolve

• Access not reduced when responsibilities narrow

• Leavers retaining system access for days (or weeks)

• Security concerns handled without HR context

• HR issues handled without security escalation

It’s rarely negligence. It’s growth outpacing structure.

Lets look at some real life examples.

Ex‑Tesla Employees Leaked 100GB of Confidential Data (2023)

Two former Tesla employees stole and leaked over 100GB of employee data, including payroll, contact details, and sensitive HR information. This occurred after they left the company, indicating a failure to immediately revoke access and remove data pathways — a core JML gap.

Capital One Data Theft by Ex‑AWS Employee (2019)

A former AWS engineer exploited a misconfigured cloud firewall to steal over 100 million customer records from Capital One.

Which highlights risks mentioned above.

• Over‑permissioned technical roles

• Cloud access not tightly governed

• High‑risk contractor/ex‑employee activity

HR Manager Created 22 Fake Employees in Payroll Fraud Scheme (Shanghai, 2025)

An HR manager at a Shanghai tech firm created 22 fake employees over eight years, redirecting payroll funds to herself (over $2.2M stolen).The scheme was discovered only when a colleague noticed one “employee” had perfect attendance.

Again demonstrating the risks highlighted in this blog.

• HR as a high‑risk access point

• Lack of audit & behavioural oversight

• Privileged administrative rights misused

• With HR overwhelmed, governance collapses

David Smith – British Embassy Security Guard Who Spied for Russia (2018–2021)

David Ballantyne Smith, a security guard at the British Embassy in Berlin, is one of the most significant UK‑linked insider‑espionage cases in recent history.

What he did:

• Began secretly collecting classified documents in 2018 while working night shifts inside restricted embassy areas.

• Copied and photographed “significant amounts” of sensitive material, including:

• Staff identities, addresses, and phone numbers

• CCTV layouts and internal office videos

• A confidential report addressed to then‑PM Boris Johnson

• Documents marked Secret and Sensitive

• Sent letters and intelligence to Russian Embassy officials in 2020, offering ongoing cooperation and more information.

• Maintained a giant Russian flag and pro‑Russia paraphernalia at home, revealing ideological motivation and strong anti‑UK sentiment.

How he was caught:

MI5 conducted a sting operation in August 2021, using undercover agents (“Irina” and “Dmitry”) posing as Russian handlers to capture Smith in the act. He was arrested shortly after.

Outcome:

• Pleaded guilty to eight Official Secrets Act offences

• Sentenced to 13 years and two months at the Old Bailey in February 2023

• UK government spent over £800,000 on immediate protective measures after the breach.

Why this is a perfect example of defence‑sector insider risk:

• Smith wasn’t a high‑ranking officer — he was a security guard, illustrating how low‑level roles with physical access can be high‑risk.

• The breach involved classified information, embassy layouts, and staff identities — all critical national‑security assets.

• His motivations blended personal grievance, ideology, and opportunism — a classic insider‑threat profile.

• The case shows how behavioural indicators (openly pro‑Russia, anti‑UK comments, isolation, resentment) went unnoticed or unaddressed.

• It demonstrates the consequences of gaps between HR, Security, and vetting processes — exactly what your document argues must be integrated.

If reading these real life examples have got you thinking about your business and the risks you have, hope fully these Practical Steps to Close the Gap will help you sleep tonight.

If not, you know who to reach out to Grigg HR.

1. Risk-Based Role Mapping

Every role should be mapped against:

• Level of system access

• Data sensitivity

• Clearance requirements

• Customer impact

HR and Security should co-own this framework — not operate separately.

2. Tight Joiners–Movers–Leavers Governance

In scaling tech and defence firms, this lifecycle must be watertight:

Joiners

• Vetting aligned to access level

• Role-based provisioning (not blanket permissions)

Movers

• Triggered review when responsibilities change

• Clearance re-check where applicable

Leavers

• Same-day access removal (system + physical)

• Exit interview aligned with risk assessment

No manual spreadsheets. No “we’ll sort it tomorrow”.

3. Integrated Tech That Supports — Not Replaces — Judgement

Used well, technology can:

• Automatically trigger access provisioning/de-provisioning

• Flag unusual access behaviour

• Track clearance expiry dates

• Maintain audit trails for defence contracts

• Create real-time compliance visibility

But here’s the important part: Tech flags. People decide.

AI can detect anomalies.It cannot assess intent, culture risk, or leadership blind spots.

That still requires experienced, senior oversight.

4. Monthly Risk Review Between HR & Security

This doesn’t need to be dramatic.

It needs to be structured.

• Emerging behavioural trends

• High-risk role changes

• Clearance updates

• Grievance patterns

• Disciplinary themes

When HR and Security talk routinely — not reactively — insider threat becomes preventative, not investigative.

This Is About Maturity — Not Paranoia

The most resilient scaling organisations in tech and defence:

• Treat HR as a risk partner, not admin

• Treat Security as strategic, not enforcement

• Align culture with compliance

• Design governance before crisis hits

Because in regulated, investor-backed, or defence-adjacent environments, the cost of “a bit of a situation” is enormous.

Financially. Legally. Reputationally. Contractually.

A Final Question for Founders and Leadership Teams

As you scale: Are HR and Security aligned by design?

Or only connected by crisis?

At Grigg HR, we support scaling tech and defence organisations that aren’t ready for a full in-house senior HR infrastructure — but absolutely need senior-level risk thinking.

We help you:

• Build joined-up governance between HR and Security

• Design proportionate, practical controls

• Strengthen joiner–mover–leaver processes

• Reduce insider risk without creating bureaucracy

• Stay compliant while scaling confidently

Practical people solutions for organisations handling sensitive data, complex growth, and real risk.

If your business is scaling and you’re not confident your HR and Security functions are truly aligned — let’s have a conversation before it becomes a problem.

Because preventing insider risk is far less painful than managing the fallout.