Vendor Due Diligence Strategy and Checklist

What Is Vendor Due Diligence?

Vendor due diligence involves assessing the risks associated with third-party vendors before forming a business relationship. It helps organizations identify potential threats, such as cybersecurity risks, financial instability, or compliance violations, and ensures that vendors meet the organization’s security, operational, and ethical standards.

The due diligence process usually involves a combination of contract review, vendor-completed assessments, and external intelligence gathering on the target company and its subcontractors. All of this is ultimately weighed against your organization’s level of risk tolerance.

Why is Vendor Due Diligence Crucial?

Third-party risks are always changing as businesses rely on an increasingly complex and diverse network of vendors, suppliers, service providers, and technology partners. As organizations grow, enter new markets, and adopt emerging technologies, their vendor ecosystem becomes more intricate, with each partner bringing unique risks.

These risks change over time due to relationship shifts and external factors like regulatory updates, economic changes, or technological progress. A partnership that was once low-risk can quickly turn high-risk because of changes in the third party’s financial stability, cybersecurity issues, or new regulatory rules.

Conducting effective due diligence on third parties enables you to identify risks before signing contracts and committing significant financial resources and time. Vendor due diligence also uncovers hidden risks in the supply chain, such as poor ESG practices or concentration risk. A mature program uses due diligence to gain visibility into its third-party ecosystem, identify unacceptable risks, and prioritize areas that require remediation.

Common Sources for Collecting Vendor Due Diligence Data:

• Vendor Risk Questionnaires: Organizations often use comprehensive questionnaires to gather information about a vendor’s internal processes, including security practices, compliance policies, and risk management protocols. These questionnaires are tailored to assess the risk profile of the third party.
• Public Databases and Registries: Public records such as government databases, corporate registries, and professional certifications provide key information about a vendor’s legitimacy, corporate structure, and compliance history.
• Financial Reports and Credit Checks: Financial stability is a significant area of concern. Organizations collect financial statements, conduct credit checks, or use services to evaluate the economic health of a third party, including factors like solvency and creditworthiness.
• Third-Party Audits and Certifications: Vendors that comply with industry standards often have third-party certifications such as ISO 27001 or SOC 2. These certifications assure a vendor’s compliance with specific security and operational standards.
• External Risk Monitoring Services: External services provide continuous risk monitoring by tracking publicly available information. They provide alerts about security breaches, legal disputes, regulatory sanctions, or negative media coverage that may impact the vendor’s risk profile.
• News and Media Reports: Media and news outlets can provide insights into vendors’ activities and any associated controversies. Negative press about environmental, social, or legal issues can indicate potential reputational risks. Investigate whether the vendor or its key individuals are subject to ongoing or past lawsuits, regulatory violations, or actions taken by agencies such as the Consumer Financial Protection Bureau (CFPB). Search for adverse news reports or articles—especially those concerning security breaches, unethical behavior, or regulatory scrutiny—that could signal reputational or operational risk.
• Industry Peers and References: Organizations may contact other vendor clients to gain insights about the vendor’s reliability, performance, and responsiveness. References provide valuable first-hand accounts of the vendor’s previous work and client relationships.
• Watchlists and Sanction Lists: Sanction lists, such as those maintained by the U.S. Treasury (OFAC), EU, or UN, help identify any legal or regulatory risks associated with a vendor. Watchlists and politically exposed persons (PEP) databases also provide information on potential compliance and reputational risks. It’s also wise to review law enforcement lists and determine if key personnel within the vendor’s organization are classified as PEPs or are named on relevant enforcement registries.
• Risk-Related Policies and Procedures: Review the vendor’s internal policies and procedures related to risk management, data security, and compliance. Understanding these frameworks gives you a clearer picture of their approach to minimizing both operational and reputational risk.
• Complaints and Negative Reviews: Check for customer complaints, negative reviews, or public dissatisfaction regarding the vendor’s services or conduct, both online and offline. These sources can reveal patterns and issues that formal reports might miss.
• Dark Web Monitoring: Dark web monitoring can help identify any compromised credentials or data breaches associated with the vendor. This source of information is critical for understanding potential cybersecurity risks.
• Site Visits and Operational Audits: For high-risk vendors, conducting onsite audits or inspections can help validate information about their operations, physical security, and adherence to best practices. This can offer a deeper understanding of how they manage processes and risks.
• Social Media and Online Reviews: Analyzing social media channels and online reviews can provide insights into public perception and customer satisfaction, which may highlight potential service or reputational risks. Additionally, monitoring the vendor’s activity on social platforms can help spot red flags, such as controversial statements or actions by company representatives.

Most procurement teams struggle to fully understand vendor risks because many pre-contract due diligence solutions provide either an internal assessment or an external financial report but not both. This fragmented view can create risky gaps and lead to potential exposure. Look for comprehensive TPRM solutions that combine external risk information with tailored risk assessment capabilities. By bringing together these methods — ranging from formal regulatory checks to assessments of public sentiment — you create a robust process for identifying political and reputational risks that could impact your organization.

Vendor Due Diligence Best Practices

Vendor due diligence can be expensive, lengthy, and time-consuming, especially for organizations that rely heavily on vendors for data handling and processing due to security implications and those with extended supply chains.

We recommend the following best practices you can employ to improve the efficiency and efficacy of your third-party due diligence process.

• Define Risk Appetite and Scope: Establish your organization’s risk tolerance to determine which third parties need thorough due diligence. Focus on criticality, data sensitivity, and regulatory requirements.
• Tier Vendors for Efficiency: Categorize vendors by risk level to allocate resources effectively. This helps you prioritize due diligence based on the importance of services and access to sensitive data. Not all vendors require the same level of scrutiny; tiering allows you to tailor your approach, ensuring that high-risk or mission-critical vendors receive more comprehensive assessments.
• Customize and Automate Risk Questionnaires: Use risk assessment questionnaires that are tailored to each vendor’s tier, industry, and the sensitivity of the data or services they access. Include questions on risk management protocols, incident response plans, history of cyber breaches, and governance practices. Where possible, automate these questionnaires to streamline onboarding and reduce administrative burden.
• Assess the Vendor Attack Surface: Analyze the external attack surface of each vendor to uncover potential security gaps in their digital infrastructure. This technical review identifies vulnerabilities that could be exploited and helps prioritize remediation efforts.
• Check for Cybersecurity Frameworks and Regulatory Compliance: Evaluate whether vendors have adopted recognized cybersecurity frameworks, such as ISO 27001, NIST, or SOC 2, or comply with regulations like GDPR, DORA, or NIS 2. This ensures a baseline standard of information security and continuous compliance.
• Continuous Monitoring, Not Just One-Time Due Diligence: Risks evolve over time. Regularly reassess vendors after onboarding and throughout the vendor lifecycle to capture new risks. Continuous monitoring — whether through automated alerts, security ratings, or periodic reviews — helps identify issues as they happen instead of waiting for annual reviews.
• Use a Repeatable Framework: Structure assessments around an industry framework, such as ISO 27001 or NIST 800-53, to ensure consistency and provide clear remediation guidelines.
• Consider Fourth- and Nth-Party Risks: Look beyond direct vendors and assess the risks posed by their vendors, known as fourth- or Nth-party risks.
• Document Risk Acceptance Internally: When business partners push forward despite risks, document the challenges and involve internal audit teams to ensure broader risk management.
• Build Strong Vendor Relationships: Foster trust by maintaining regular communication, treating vendors as partners, and sharing insights to improve collaboration. Supply chains are only as strong as their weakest link, so understanding the extended ecosystem is essential.
• On-Site Visits and Operational Audits When Necessary: For high-risk or high-impact vendors, conduct on-site visits to assess physical and technical security controls and validate operational practices. These audits offer more profound insights into how vendors protect your data and manage risk on a day-to-day basis.

By adopting a risk-based, tiered approach and leveraging both automation and continuous monitoring, your organization can enhance due diligence outcomes, allocate resources where they matter most, and maintain a proactive stance against an ever-evolving risk landscape.

Review Employee Practices for Better Risk Management

When evaluating a vendor, consider looking into their employee management protocols. After all, even the best technology or processes can be compromised by poor human practices.
Key employee practices to examine include:

• Hiring and Background Checks: Determine whether the vendor conducts thorough background screenings on all employees, particularly those with access to sensitive data or systems. Gaps here could leave you exposed to insider threats or compliance violations.
• Cybersecurity and Awareness Training: Ask about the frequency and depth of cybersecurity training provided to employees. Considering that privilege misuse and human error remain leading contributors to security breaches, vendors must provide regular, up-to-date training aligned with frameworks such as ISO 27001 or guidance from organizations like ISACA.
• Access Controls and Privilege Management: Scrutinize how access to critical systems and data is granted, maintained, and revoked. Does the vendor follow the principle of least privilege? Are there regular audits of user access rights?
• Incident Response and Notification Protocols: Ensure the vendor’s staff are familiar with incident response procedures, including how and when to notify clients of any data breach or compromise caused by employee actions.

By verifying these employee-related practices, you strengthen your understanding of the vendor’s overall risk posture — and can be more confident that the people on the other side are equipped to protect your interests.

When Should You Conduct Vendor Due Diligence?

Companies should conduct vendor due diligence at several key points during their relationship with a third party to ensure ongoing risk management and compliance. Here are the critical stages when vendor due diligence is necessary

1. Before Onboarding (Pre-Contract Due Diligence)

Pre-contract due diligence is crucial. Before entering into a contract with a new vendor, companies should perform thorough due diligence to assess any potential risks the vendor may pose to the business. This includes evaluating the vendor’s financial stability, security practices, compliance with relevant regulations, and reputation. This step helps prevent future issues and ensures the vendor can meet contractual obligations.

2. During Onboarding

Businesses must evaluate a vendor’s practices when onboarding. This involves assessing outstanding documentation, validating regulatory compliance, and confirming that the vendor is ready to begin the contract. Conducting onboarding due diligence helps align both parties on expectations and responsibilities, avoiding potential future issues.

3. Ongoing Monitoring (During the Vendor Relationship)

Due diligence shouldn’t be a one-time process. Continuous monitoring can include periodic reviews of their financial health, security protocols, compliance status, and any new developments that could affect the organization. Regular monitoring ensures the vendor meets the company’s standards throughout the relationship.

4. When Significant Changes Occur

Companies should conduct due diligence if significant changes to the vendor’s operations, structure, or business environment exist. Examples include mergers, acquisitions, changes in leadership, or shifts in the market or regulatory landscape. These changes may introduce new risks that need to be evaluated.

5. Before Renewal or Extension of Contracts

When renewing or extending a contract with an existing vendor, due diligence is essential to confirm that the vendor meets all necessary compliance, security, and operational standards. It also ensures that no new risks could affect the company’s operations.

6. When Adding New Services or Expanding Vendor Scope

Suppose a vendor is going to take on new services, access more sensitive data, or expand their role within the company. In that case, the company should conduct due diligence to assess the new risks associated with this change. This is particularly important when vendors handle more critical aspects of the business or access more valuable data.

7. When Considering Third-Party Risk Exposure (e.g., Fourth-Party Risks)

If a vendor relies on third parties to deliver services (e.g., subcontractors), extend due diligence to these vendors, known as fourth or Nth parties. Evaluating the risks these secondary vendors may pose to the organization is essential.

Vendor Due Diligence Checklist

Vendor due diligence is a critical process that involves identifying and assessing the potential risks from third-party vendors, partners, or service providers. The goal is to ensure that these third parties do not expose your organization to undue risk. Typical due diligence activities include:

• Identify Third-Party Vendors & Suppliers: List all vendors and suppliers along with their roles and services.
• Collect Basic Information: Gather information from the third party to evaluate their ability to meet your requirements: request risk questionnaires, financial reports, and certifications (e.g., ISO 27001, SOC 2).
• Assess the Level of Risk: Determine the level of risk each third party poses to your organization. Consider factors such as the criticality of their services, access to sensitive data, geographic location, and regulatory exposure.
• Screen for Compliance & Reputational Issues: Check sanction lists and perform adverse media checks for potential reputational issues.
• Review Policies & Controls: Examine vendor policies related to security, data protection, and business continuity.
• Review Contracts: Ensure that the contracts with third parties include clauses that mitigate potential risks.
• Perform Background Checks: For critical vendors, conduct checks on key personnel.
• Make an Informed Decision: Decide whether to proceed, decline, or add conditions based on the findings.
• Document & Report Findings: Maintain a record of all assessments and decisions made during due diligence.

Determine the breadth and depth of these activities based on each vendor’s potential impact on your organization. If applicable, establish a baseline of your current vendor network to inform future due diligence practices.

Enhance Due Diligence with a Unified Approach

Mitratech’s VRM solution is a complete vendor due diligence solution that unifies third-party risk assessment results with financial, cyber, operational, ESG, and reputational monitoring for a continuous, closed-loop view of vendor risks.

With Mitratech, you can:

• Accelerate pre-contract due diligence with centralized insights into vendor cybersecurity, operational, and compliance risks.

• Make informed vendor profiling, tiering, and categorization decisions with accurate due diligence.

• Simplify due diligence by assessing third parties against multiple risk types in a single solution.

• Reduce costs by uniting risk assessments and continuous monitoring in a single solution.

• Continuously monitor offboarded third parties to reduce risk in the long term.

Learn more about our approach in our best practices guide, or request a demo to see how Mitratech can take the pain out of your vendor risk management initiatives.

Editor’s Note: This post was originally published on Prevalent.net. In October 2024, Mitratech acquired the AI-enabled third-party risk management, Prevalent. The content has since been updated to include information aligned with our product offerings, regulatory changes, and compliance.