You can have the best cybersecurity tools, the strongest firewalls, and the most disciplined team—but none of that matters if a vendor you trust leaves the door open.
In 2025, cybercriminals are increasingly targeting small businesses through their vendors, partners, and service providers. These third-party attacks exploit shared access, unsecured applications, and weak security practices to bypass your defenses—sometimes without you ever realizing it.
If your vendors aren’t secure, your business isn’t either. In this blog, we’ll break down what third-party risk is, why it matters more than ever, and what small businesses can do to protect themselves.
What Is Third-Party Cyber Risk?
Third-party cyber risk refers to the vulnerabilities introduced by any external vendor, contractor, or partner that has access to your systems, data, or network. These can include:
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Cloud service providers
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Payment processors
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HR or payroll companies
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Managed IT providers
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Software vendors
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Freelancers and contractors with access to company files
These partners may not fall under your internal security policies—but their actions (or lack thereof) can directly affect your business. Cybercriminals know this and increasingly use vendors as a “backdoor” into otherwise secure environments.
Why This Threat Is Growing in 2025
Several trends are making third-party risk more dangerous than ever:
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Remote & Cloud-First Workflows: More vendors now access your systems via the cloud, increasing exposure.
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Tool Overload: SaaS sprawl has led to hundreds of connected apps—many unknown to IT.
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Targeted Supply Chain Attacks: Threat actors are going after small and midsized vendors with the goal of reaching larger targets.
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Cyber Insurance Pressure: Insurers now want proof that you’re managing your vendor relationships and access.
Recent high-profile attacks like the MOVEit breach and SolarWinds compromise show how a single vendor’s weak link can ripple across thousands of businesses. Small companies are no exception—and are often less prepared.
Real-World Examples of Vendor Breaches
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A cloud file-sharing service used by a local business is breached, exposing sensitive client contracts.
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A third-party HVAC vendor connects to your network for remote diagnostics—but their laptop is infected with malware.
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A payment processor suffers a phishing attack, redirecting client payments to fraudulent accounts.
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A contracted marketing firm uploads credentials to an unsecured cloud folder, which is indexed by search engines.
Each of these examples is real—and could have been avoided with proper vendor management.
How to Manage Third-Party Risk
You don’t need to cut off every outside vendor to stay secure. But you do need a plan. Here are key best practices:
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Vendor Due Diligence: Screen vendors before onboarding. Ask for their security policies, incident response plans, and certifications (e.g., SOC 2, ISO 27001).
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Limit Access: Apply the principle of least privilege—only grant vendors the access they need, and nothing more.
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Multi-Factor Authentication (MFA): Require MFA for any vendor with system or data access.
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Security Questionnaires: Send annual or quarterly questionnaires to critical vendors to monitor risk.
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Contract Clauses: Include cybersecurity requirements in service-level agreements (SLAs), including breach notification timeframes.
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Audit and Monitor: Periodically review which vendors have access to what—and revoke access when no longer needed.
How MSPs Like V2 Systems Help
Managing vendor risk can be overwhelming, especially for smaller businesses without a dedicated security team. That’s where V2 Systems comes in.
We help you:
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Identify and inventory your third-party vendors
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Set up secure access controls and MFA for external parties
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Create policies and SLAs that hold vendors accountable
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Monitor for unusual activity tied to third-party accounts
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Ensure your business meets security standards for insurance and compliance
Whether you need help writing your first vendor policy or auditing access across systems, we’ve got your back.
Learn more about our Managed Compliance Services
Check out our Ultimate SMB Cybersecurity Checklist
Conclusion: Trust—but Verify
In a connected world, no business operates alone—but that doesn’t mean you have to sacrifice security for convenience. By actively managing vendor risk, you protect your company, your clients, and your reputation.
Remember: your security posture is only as strong as the weakest link in your supply chain. Don’t let someone else’s mistake become your biggest headache.
👉 Contact V2 Systems for a free two-hour cybersecurity consultation to assess your third-party risk exposure.
👉 Continue reading: The Ultimate SMB Cybersecurity Checklist
