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How A Supplier’s Cybersecurity Flaws Could Jeopardize Your Business

Written by Lisa Carroll | November 7, 2025

Although you may think your cybersecurity defenses are strong, even the most powerful security tools and systems may be of little protection if your third-party vendors and suppliers don’t have similarly robust safeguards in place.

That’s because threat actors understand that one of the most effective ways to attack a high-profile target is to take a backdoor approach by going after smaller intermediaries that are linked to them.

Rather than waste time and energy trying to break through an organizations strong technical security defenses, they simply find a workaround to bypass those cybersecurity guardrails entirely. In many cases—the shortcut ends up being those third-party subcontractors, vendors, suppliers, and other affiliated organizations.

In this article, we’ll examine how bad actors can exploit the cybersecurity weaknesses of connected suppliers and similar companies, and how such exploitation can have a ripple effect with real consequences to your business.

How Can My Suppliers’ Weak Cybersecurity Posture Affect My Business?

A third party can be a supplier, vendor, contractor, or any other external organization that your company uses for various hardware, software, applications, services, and support.

These companies can include cloud hosting vendors, HR and payroll services, call center support, customer relationship management (CRM), payment processing, and logistics services, just to name a few.

If you’re a prime contractor or other business that works with third-parties that have access to your network, then their cybersecurity deficiencies could become a real cause for concern for your business.

Aided by advanced technologies, including artificial intelligence (AI), cyber attackers are finding new ways to trick unsuspecting users into disclosing sensitive information, or take some harmful action that could allow them unauthorized access to your network.

Once inside, these cybercriminals can then launch a larger cyberattack such as ransomware or malware that affects multiple companies within the supply chain.

These attacks can lead to prolonged downtime and operational disruption, lost revenue, and the possibility of your data being stolen or compromised.

As recent supply chain attacks have shown, the damage can be catastrophic.

For instance, the fallout is still being felt from the Change Healthcare cyberattack in February 2024 that rocked the healthcare industry, the CDK Global cyberattack that hit the auto industry in June 2024, and the recent spate of Scattered Spider cyberattacks that have affected various industries.

All of the those attacks have resulted in billions of dollars in financial losses. They have also left many companies teetering on the brink of failure. Other organizations, unable to recover, were forced to shutter their doors permanently.

What Are Specific Third-Party Cybersecurity Risks?

Third-party cybersecurity risks can inadvertently put your organization at risk.

Those risks include potential data breaches leading to stolen or compromised sensitive information. Cybercriminals often strike third-party vendors as a backdoor way to launch a supply chain attack that uses malicious code spread through malware on software or hardware.

These workarounds allow cyber attackers a way to bypass your strong cybersecurity controls to gain unauthorized access into your systems and databases.

A common tactic used by threat actors to gain initial access to a third-party vendor or organization is to use a phishing scheme with AI-backed technology. This advanced create sophisticated, highly convincing, images, emails, voicemails, text messages, videos, and other fake communication.

Attackers attempt to trick an employee at a third-party organization to unwittingly click on an infected link or download a malicious file that can spread the malware like wildfire throughout the supply chain.  

Once an employee at a connected company takes the bite, hackers can gain unauthorized access into their network, then lie in wait to launch a larger, supply chain attack.

Many small and medium-sized organizations stand to benefit from partnering with a managed IT services provider (MSP) to help mitigate risks associated with working with third-party companies.

What Other Concerns Should Businesses Have About Third-Party Companies?

Many cybersecurity and data privacy regulations require prime contractors to make sure that their subcontractors with flow-down of certain sensitive information, have put in place the right security protections to minimize the risk of cybersecurity threats.

The Cybersecurity Maturity Model Certification (CMMC) 2.0, for instance, requires subcontractors with flow-down of federal contract information (FCI) and controlled unclassified information (CUI) to implement the same robust cybersecurity protections as the prime contractor.

Similarly, primes within the healthcare industry are responsible under HIPAA for verifying that their subcontractors that handle electronic protected health information (ePHI) have proper cybersecurity measures in place to ensure that the sensitive information stays secure.

What’s more, cyber liability insurance also often requires stringent cybersecurity controls to lessen the chances of a cyberattack. Failure to comply with the various regulatory and cyber insurance mandates can lead to significant penalties, fines, and even potential legal consequences.

How Can Managed IT Minimize Third-Party Cyber Risks?

According to Verizon’s 2025 Data Breach Investigations Report, 30 percent of data breaches originated from third parties, double the amount from the previous year. The report also found that about a third of the time (34 percent), hackers were able to exploit vulnerabilities to gain unauthorized access.

While third party cyberattacks are less common than attacks targeting businesses directly, they represent a rising trend.

With managed IT services, you can establish a robust cybersecurity posture to protect your business and keep your sensitive information out of the wrong hands.

Internal Risk Assessment:

    • Evaluate the health and security of your IT systems, software, and hardware
    • Install the right tools, systems, and devices to enhance your cybersecurity readiness and minimize threat risks

Vendor Inventory & External Risk Assessment:

    • Review your third-party vendors to determine what parts of your network and databases they are able to access
    • Assess the cybersecurity strength of third parties connected to your business
    • Establish strong cybersecurity guardrails such as multi-factor authentication, role-based access controls, and network segmentation, among others

Managed Network Monitoring:

    • Automated, continuous network monitoring helps keep your network secure by providing proactive monitoring for potential threats and irregularities.
    • A signal is sent out to alert the MSP’s stakeholders when potential threats or issues are detected within your hardware, software, or systems.
    • With network monitoring, potential threats are blocked automatically while others are quarantined for further evaluation by your MSP.

Incident Response Plan:

    • Many cybersecurity regulations and cyber insurance require businesses to have an incident response plan (IRP) in place.
    • An IRP is essentially a roadmap for what steps your organization will take in the event of a cyber incident
    • An MSP can help you develop and implement an IRP so that you can recover quickly from a cyber incident, minimize disruptions and downtime, and return to normal operations quickly.

Specialized IT Expertise:

    • Gain a team of IT and cybersecurity professionals with specialized skills and knowledge of industry best practices to put the right IT tools, systems, and devices in place to protect your business and valuable data.
    • Ensures that you meet regulatory and insurance cybersecurity requirements
    • Helps you gain a competitive advantage by minimizing risks and maximizing uptime

What You Should Do Next to Protect Against Third-Party Cyber Threats

In this article, we’ve outlined the main concerns when using third parties and how to reduce those threat risks using managed IT services.

We understand, however, that managed IT may not be the right fit for every business.

That said, if you own a small or medium-sized business, and you’re not currently using a managed IT service provider and don’t have sufficient—or any internal IT staff—managed IT could be the right solution for your organization.

On the other hand, if you are currently working with an MSP, but the relationship has reached a breaking point, you may be looking for a new managed IT company.

If so, consider several important criteria, including your IT needs, your short and long-term business goals, your internal IT staff expertise and availability, and your IT budget.

Read this article to learn more about why more small and medium-sized businesses are turning to managed IT.

If you need help evaluating your cybersecurity defenses to protect against third-party supply chain breaches or other cybersecurity threats, let’s connect.

Reach out to us now to start a conversation about your IT challenges so we can determine how we can help you solve them.