slug: “third-party-risk-management-how-to-assess-external-vendor-security” Modern business is a complicated, global network of interdependencies. No company operates in a vacuum anymore. We rely on dozens, often hundreds, of external vendors who provide us with key products and services - from SaaS software and cloud platforms, through IT support, to legal and marketing services. We entrust them with our most valuable data, give them access to our systems, and trust that they will treat our security with the same seriousness as we do ourselves. However, the history of recent years, marked by catastrophic supply chain attacks such as the SolarWinds incident, has brutally verified this naive assumption.
It turned out that the easiest path to a fortified fortress is often to bribe or deceive a trusted vendor who has a legitimate key to it. In response to this growing, systemic risk, European legislators, through regulations such as NIS2 and DORA, have made a fundamental shift, transferring part of the responsibility to companies that use vendor services. Third-Party Risk Management (TPRM) has ceased to be a good practice and “nice addition.” It has become a hard, legally enforceable obligation and one of the most important pillars of a mature cyber resilience strategy.
Quick Navigatio
What is Third-Party Risk Management (TPRM) and why is it so critical today?
Third-Party Risk Management (TPRM), also known as vendor risk management, is a comprehensive business process whose goal is to identify, assess, mitigate, and continuously monitor risks associated with cooperation with external vendors, partners, and subcontractors. In the context of cybersecurity, a TPRM program focuses on risks arising from vendors’ access to our data, systems, and networks, as well as on the security of the software and hardware we purchase from them. It is a proactive discipline that replaces blind trust with structured verification and shifts security responsibility to the entire ecosystem in which the company operates, not just its internal infrastructure.
This is so critical today because attackers consistently choose the path of least resistance. As companies strengthen their own security, their vendors become increasingly attractive targets. Compromising one vendor can have a cascading effect, leading to the compromise of dozens or hundreds of its clients in one fell swoop. Without a formal TPRM program, a company is blind to risks hidden in its supply chain.
How do regulations like NIS2 and DORA force TPRM implementation?
New EU regulations make TPRM a hard legal requirement. The NIS2 Directive (and its Polish implementation in the National Cybersecurity System Act) explicitly lists “supply chain security” as one of ten mandatory areas that essential and important entities must manage. It requires organizations to account for vulnerabilities specific to each vendor and assess the overall quality of their cybersecurity practices.
The DORA Regulation for the financial sector goes even further, dedicating an entire, extremely detailed chapter to managing risk from external ICT vendors. It imposes very specific obligations on financial institutions, such as maintaining a detailed contract register, conducting in-depth risk assessment before contracting, and including a number of mandatory clauses in contracts. These regulations in practice mean that the lack of a documented TPRM program is now a serious legal non-compliance.
How to start, or how to conduct vendor inventory and categorization?
You cannot manage what you don’t know exists. Therefore, the absolutely first step in building a TPRM program is creating a complete inventory of all ICT vendors. This process often reveals that the company uses significantly more tools and services than anyone suspected (“Shadow IT”). Information should be gathered from the IT department, procurement, finance, and individual business departments.
Next, crucially, not all vendors are equal. Attempting to subject each of them to the same rigorous assessment process would be inefficient and extremely costly. Therefore, risk categorization must be performed. Each vendor should be assigned to one of several categories (e.g., critical, high, medium, low) based on two main factors: data access (what type of data and in what quantity does the vendor process?) and service criticality (how much does our company’s operations depend on the service provided by this vendor?). This categorization will allow for proportionate application of controls.
What does the due diligence process involve and how to assess a new vendor?
The due diligence process is the assessment phase that takes place before signing a contract with a new vendor. Its purpose is to verify whether the potential partner meets your company’s minimum security standards and whether cooperation with them will not introduce unacceptable risk. This process should be structured and evidence-based. It typically begins with sending the vendor a security assessment questionnaire. In addition, you should request objective evidence of the declared security state, such as certificates (e.g., ISO 27001), audit reports (e.g., SOC 2), or penetration test results. For vendors of highest criticality, consider conducting a dedicated audit or conversations with their security team.
What role do security questionnaires and standards (CAIQ, SIG) play?
A security assessment questionnaire is a basic tool in the due diligence process. Instead of creating questions from scratch, it’s worth relying on recognized industry standards that ensure comprehensiveness and facilitate comparison of responses from different vendors. Among the most popular and comprehensive are: Consensus Assessments Initiative Questionnaire (CAIQ), developed by the Cloud Security Alliance (CSA), which is ideal for assessing cloud service providers, and Standardized Information Gathering (SIG) Questionnaire, which is another very popular and scalable standard. Using these structured questionnaires ensures that no key area is overlooked - from risk management, through access control, to incident response.
What security clauses must be included in vendor contracts?
The vendor contract is the legal foundation of the relationship and a key tool for enforcing security requirements. The legal department, in cooperation with the security team, should develop a standard set of security clauses to be attached to all ICT vendor contracts. Among the most important provisions that should be included in the contract are requirement to comply with specified security standards, right to audit, incident reporting obligations (with clearly defined SLAs), business continuity requirements, data security clauses (encryption, location), and provisions specifying the vendor’s financial liability for damages resulting from breach of security obligations.
Why is assessment at contract signing not enough, and what is continuous monitoring?
A vendor’s security assessment at the time of contract signing is only a “snapshot” of their state at a given point in time. Every company’s security posture is dynamic - it can improve or, worse, deteriorate. That’s why a mature TPRM program must include a continuous monitoring element. This process includes periodic re-assessments (e.g., annual questionnaire submissions). Automated Security Rating platforms, which continuously and non-invasively scan the vendor’s external security posture, alerting to new vulnerabilities or configuration errors, are playing an increasingly important role. Public information should also be monitored for reports of security incidents at our key partners.
How to interpret certificates and reports such as ISO 27001 and SOC 2?
Certificates and audit reports are objective, third-party-verified evidence of vendor maturity. However, one must know how to read them. An ISO/IEC 27001 certificate proves that the vendor has an implemented and functioning Information Security Management System (ISMS), meaning they have structured, risk-based processes. A SOC 2 report, especially Type II, is even more valuable - it not only describes the controls implemented by the vendor but also contains an independent auditor’s opinion on their operational effectiveness over an extended period of time. When analyzing these documents, attention should be paid to the audit scope and any exceptions or non-conformities noted by the auditor.
What is fourth-party and -th party risk and how to deal with it?
Your risk doesn’t end with your direct vendors. Fourth-party risk is risk associated with your vendors’ subcontractors. For example, if you use the services of a SaaS company, and they host their application in AWS cloud, then AWS becomes your fourth-party vendor. An outage or incident at AWS can directly affect the service you use. Managing this risk is extremely difficult because you don’t have a direct contractual relationship with these entities. The key is transferring responsibility to your direct vendor. In the assessment process and contract, you should require that your vendor has their own mature TPRM program and actively manages the security of their key subcontractors.
What tools (TPRM platforms, Security Ratings) can automate this process?
At scale, manually managing hundreds of vendors using spreadsheets is inefficient and error-prone. The market has an entire category of specialized Third-Party Risk Management (TPRM) Platforms. These tools automate the entire lifecycle - from sending questionnaires, through analyzing responses and tracking remediation actions, to continuous monitoring. A complement is Security Rating services (e.g., SecurityScorecard, BitSight), which act like a “rating agency” for cybersecurity, providing an objective, external assessment of the vendor’s security posture.
How to prepare for a security incident whose source is a vendor?
One should assume that one of our vendors will eventually fall victim to an attack. It is crucial that the company’s Incident Response (IR) Plan accounts for such a scenario. The plan must clearly define communication procedures with the vendor in a crisis situation. Who is the contact person on both sides? Within what time is the vendor obligated to inform us of an incident? What information must they provide us? Conducting joint tabletop exercises with key vendors, during which incident response procedures can be practiced in safe conditions, is extremely valuable.
Frequently Asked Questions
How often should vendor security assessments be conducted?
Critical and high-risk vendors should be reassessed at least annually, with continuous automated monitoring in between. Lower-risk vendors can follow a biennial cycle. Any significant change in the vendor’s services, a reported security incident, or a major regulatory update should trigger an immediate reassessment regardless of the regular schedule.
What is the difference between ISO 27001 certification and a SOC 2 Type II report?
ISO 27001 certifies that a vendor has implemented a structured Information Security Management System based on risk assessment. A SOC 2 Type II report goes further by providing an independent auditor’s opinion on the operational effectiveness of specific security controls over a defined period, making it a more detailed evidence of actual security practices.
How should small organizations with limited resources approach third-party risk management?
Small organizations should start by identifying their most critical vendors — those with access to sensitive data or systems — and focus assessment efforts there. Using standardized questionnaires like SIG Lite and leveraging Security Rating platforms for automated monitoring can provide meaningful oversight without requiring a large dedicated team.
What are the key contractual clauses to include for vendor security?
Essential clauses include the right to audit, mandatory incident notification timelines (ideally within 24-48 hours), data processing requirements aligned with GDPR and NIS2, subcontractor approval rights, and clearly defined liability and indemnification in case of a security breach originating from the vendor.
Read Also
- ‘How to Effectively Manage Risk in Projects: Building Organizational Resilience’
- Risk Management Practices That Can Help Minimize Potential Problems During IT Project Execution
- Risk Management Practices That Can Help Minimize Potential Problems During IT Project Implementation
Develop Your Skills
This article is related to the training KSeF - Strategic Implementation Project and Risk Management. Check the program and sign up to develop your skills with EITT experts.