Richard’s post — est. reading time: 10 min

Modern software is not built from scratch. It is assembled—from open-source libraries, vendor APIs, third-party services, and automation tools. Each one of these components, while invaluable to speed and innovation, introduces potential risk. And the more we integrate, the larger and more complex our attack surface becomes. This reality has given rise to one of the most pressing and underappreciated challenges in contemporary software delivery: supply chain security.

In today’s interconnected development ecosystems, attackers don’t always break through the front door. Increasingly, they ride in quietly through trusted dependencies. What makes supply chain threats so dangerous is precisely their subtlety. They are often invisible—hiding within signed packages, approved vendor tools, and automated deployment scripts. And when they are exploited, the impact is severe.

When Trust Becomes a Threat: A Global Wake-Up Call

One of the most sobering examples of supply chain risk played out in a now infamous incident that reverberated across governments and global enterprises. A sophisticated attacker compromised a trusted software supplier by embedding malicious code into its update pipeline. The tainted software was then signed, distributed, and deployed by thousands of unsuspecting customers. It looked legitimate. It behaved normally. And it went undetected for months.

The consequences were devastating. Critical systems across finance, defence, and technology sectors were compromised. The breach required months of forensic investigation and sparked urgent calls for greater supply chain accountability. What made the breach particularly alarming was not its technical complexity, but its strategic cunning. The attacker didn’t breach the systems directly. They waited for trusted systems to invite them in.

This is the defining risk of supply chain compromise: it bypasses traditional security assumptions. Firewalls, endpoint protection, and identity controls are powerless against a malicious update served by a trusted source.

Third-Party Code: Essential but Dangerous

It’s unrealistic to abandon third-party tools or rewrite every library internally. Open-source software has become the bedrock of innovation. Vendor integrations power everything from payments to analytics. The key isn’t to avoid third-party code—it’s to understand and manage its risk.

But therein lies the challenge. Unlike your own code, third-party components are often opaque. Their security practices, update policies, and vulnerability disclosures may be inconsistent—or absent entirely. As dependencies multiply, so do the unknowns.

• Are all your components still maintained?
• Are any of them pulling in sub-dependencies that you’ve never reviewed?
• Would you know if one of them changed ownership or introduced malicious code?

These questions are difficult to answer without the right processes, tooling, and visibility.

Executive Insight: Why “Trust” Is Not a Strategy

From the boardroom to the sprint planning session, one principle must be clear: security cannot be assumed. The idea that third-party components are “safe until proven otherwise” is a liability. Instead, organisations must shift to a mindset of cautious validation—“trust, but verify.”

For executives, the risk is both technical and reputational. A single breach through a dependency can undermine customer confidence, damage brand equity, and lead to regulatory scrutiny. It doesn’t matter whether the vulnerability originated in your code or someone else’s—the accountability is yours.

Executive leaders must ensure their security strategies account for the full software supply chain. That includes enforcing due diligence on vendors, visibility into code dependencies, and clear ownership of third-party risk management.

How to Address Third-Party and Supply Chain Risk

Managing supply chain security requires a layered, continuous approach. It’s not a checklist—it’s an ongoing capability. Here are the core pillars of effective defence:

1. Establish a Software Bill of Materials (SBOM)
You can’t secure what you don’t know you depend on. An SBOM is a detailed inventory of all third-party components, libraries, and tools used within your codebase. It provides a clear picture of your dependencies—and helps identify when a newly disclosed vulnerability affects your systems.

2. Implement Software Composition Analysis (SCA)
SCA tools automate the discovery and monitoring of third-party risks. They scan dependencies against known vulnerability databases and flag outdated or risky components. This should be integrated into your CI/CD pipeline so developers receive immediate feedback when a new package introduces risk.

3. Conduct Vendor Risk Assessments
For commercial software providers, formal risk assessments are essential. Evaluate their security controls, patching practices, compliance certifications, and breach history. Require suppliers to disclose how they manage their own supply chain risk. Security questionnaires, audits, and contracts should reflect these expectations.

4. Require Attestations and Secure Development Standards
Internal and external software suppliers should adhere to secure development principles. Frameworks like the Secure Software Development Framework (SSDF) or the OWASP Software Assurance Maturity Model (SAMM) provide structured guidance. Security attestations—statements confirming adherence to specific controls—create accountability.

5. Prepare for Supplier Incidents
Even with the best defences, compromises can happen. That’s why incident response plans must include supplier breach scenarios. Teams should know how to identify when a third-party tool has been compromised, how to isolate affected systems, and how to communicate with stakeholders. Having a predefined playbook reduces panic and improves response time.

Integrating Supply Chain Security Into DevSecOps

Supply chain risk isn’t separate from DevSecOps—it must be embedded within it. That means treating third-party analysis as a standard part of the pipeline. Security tools should automatically flag risky dependencies. Policies should block builds that include known high-severity vulnerabilities. Updates to libraries should trigger reviews—not just for technical compatibility, but for security posture as well.

Security champions within engineering teams can help build awareness around supply chain risks. They can guide peer reviews that include dependency scrutiny, and help normalise conversations about vendor security during sprint planning and retrospectives.

The Cultural Shift: Security is Everyone’s Job

One of the biggest obstacles to effective supply chain security is the assumption that “someone else is handling it.” In high-performing teams, everyone—from developers to product managers—understands the role they play in securing dependencies. That cultural shift begins with education, continues with empowerment, and is reinforced through shared responsibility.

Make secure development visible. Celebrate teams that remove risky libraries. Train developers on how supply chain attacks work. Make supply chain risk part of engineering health reviews—not just security audits.

A Final Reflection

Your software is only as secure as its least secure component. That component might not be yours. It could be buried five layers deep in an open-source dependency, or sitting quietly in a vendor’s deployment script. If you’re not managing that risk proactively, you’re not managing it at all.

Supply chain security may be silent—but its impact is not. Don’t wait for a breach to take it seriously.