Why Your Business Could Be the Weakest Link in Someone Else's Supply Chain

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You Might Not Be the Target — But You Could Be the Way In

You might not think of your business as an attractive target for a cyber attack. You're not a bank. You don't hold millions of customer records. You're just a business trying to get on with things.

But here's the reality. Attackers often don't want you. They want your client. And you're the way in.

Supply chain attacks — where criminals compromise a smaller supplier to reach a larger target — are one of the fastest growing threat patterns in cyber security. And SMEs are frequently the entry point.

Why SMEs Are in the Crosshairs

Large enterprises spend significant money on cyber security. They have dedicated teams, mature processes, and layers of technical controls. Breaking in directly is hard.

Their suppliers are a different story.

A mid-sized law firm, a regional logistics company, an IT support provider, a marketing agency. These businesses often have access to a larger organisation's systems, data, or communications. They receive and send emails on their behalf. They log into client portals. They handle sensitive documents.

If an attacker can compromise one of those suppliers, they can use that access as a launchpad. The target organisation trusts the supplier. The emails look legitimate. The access looks normal. By the time anyone notices, it's too late.

What Does a Supply Chain Attack Actually Look Like?

It helps to make this concrete.

A common scenario involves business email compromise. An attacker gains access to an account at a supplier, monitors email traffic for weeks, then steps in at the right moment to redirect a payment or intercept a sensitive conversation. The recipient thinks they're talking to someone they know and trust.

Another pattern involves software or tools. If your business uses a piece of software that gets compromised at the vendor level, that compromise can flow through to every customer using it. The SolarWinds attack in 2020 is the most well-known example, but the pattern has been repeated many times since at a smaller scale.

A third involves direct access. Many suppliers have credentials to log into client systems — whether that's a shared document platform, a finance system, or a project management tool. If those credentials are stolen or the supplier account is compromised, the attacker inherits whatever access the supplier had.

What Can SMEs Do About It?

The good news is that reducing your supply chain risk doesn't require enterprise-level resources. It requires a clear-eyed look at a few key areas.

Know what access you've given out. Start by listing the third parties who have any form of access to your systems, data, or communications. Many businesses are surprised by how long that list is. Once you know who has access, you can review whether it's still needed and whether it's appropriately restricted.

Apply the principle of least privilege. This simply means giving people and systems only the access they actually need — nothing more. If a supplier needs to access one folder in SharePoint, they shouldn't have access to the whole environment. Tightening this up reduces the blast radius if something goes wrong.

Ask your key suppliers the right questions. You don't need to conduct a full audit of every supplier. But for the ones with meaningful access to your business, it's reasonable to ask whether they have basic security controls in place. Do they use MFA? Do they have a security policy? Have they ever experienced a breach? Their answers — and how they respond to being asked — tell you a lot.

Be alert to unusual requests via email. A significant proportion of supply chain incidents involve impersonation or account takeover. If a trusted contact suddenly asks you to change bank details, make an urgent payment, or share login credentials, treat it as suspicious regardless of who it appears to come from. Pick up the phone and verify.

What Should You Do Next?

Supply chain risk is one of those areas where awareness is half the battle. Most SMEs haven't mapped their third-party access, haven't asked their suppliers about security, and haven't thought about how an attacker might use them as a stepping stone.

That doesn't make them negligent. It makes them normal. But it does mean there's usually straightforward work to do.

If you'd like help understanding your supply chain exposure and where to focus first, we're happy to have that conversation. No jargon, no lengthy engagement — just a clear picture of where you stand and what to fix first.