Vendor management may be reviewed by assurance practitioners, regulators, and customer security or procurement teams, depending on your product, data, contracts, and market.
This guide explains why, what they look for, and how to be ready.
Why Enterprises Review Vendor Compliance
Third parties are one part of the attack surface. NIST's supply-chain guidance addresses intentional and unintentional risks in acquired products and services, including vulnerable development practices, tampering, counterfeit components, and supplier dependencies.
Customer questionnaires often ask how a supplier identifies, assesses, contracts with, monitors, and exits its own critical providers. The depth varies by customer and risk.
Your vendor management program is evidence of your operational maturity. A company that cannot articulate how they manage their own vendor risk is a company that enterprise buyers view as a potential liability.
What a Customer Security Review Will Ask
Customer security questionnaires follow a fairly standard structure. The vendor management questions you should expect:
Do you have a formal vendor management policy? They want to see that vendor risk management is a documented process, not an ad hoc practice.
How do you assess vendor risk? Risk classification, due diligence procedures, and criteria for enhanced review of high-risk vendors.
What controls do you require vendors to have? Insurance requirements, security certifications, contractual security terms, audit rights.
How do you monitor vendor compliance ongoing? Are documents tracked for expiration? Is there a periodic re-assessment process? Who is responsible?
What is your process for vendor offboarding? How do you revoke access when a vendor relationship ends?
Do you track which vendors have access to customer data? Can you produce a list of vendors with data access, with evidence of the controls in place for each?
What SOC 2 and ISO 27001 Auditors Look For
If you are pursuing a SOC 2 examination or ISO/IEC 27001:2022 certification, supplier risk can be relevant to the selected criteria, scope, and risk treatment.
SOC 2 CC9.2 states that the entity assesses and manages risks associated with vendors and business partners. The AICPA points of focus discuss engagement requirements, responsibilities, communication, performance, change, and termination; they do not mandate one evidence package for every vendor.
ISO/IEC 27001:2022 is the current information-security management-system requirements standard. Supplier-related controls in the 2022 control set are numbered A.5.19 through A.5.23, not the superseded Annex A.15 numbering from the 2013 edition. Applicability is determined through the organization's risk treatment and Statement of Applicability.
Auditors for both frameworks will ask for:
- A vendor inventory, particularly for vendors with data or system access
- Evidence of due diligence (security questionnaires, SOC 2 reviews, etc.)
- Contracts with data handling terms
- Evidence of ongoing monitoring (expiration tracking, periodic re-assessments)
The difference between a clean audit finding and a finding with exceptions is usually not the existence of controls; it is whether the controls are documented, systematic, and evidenced.
What Prospects Ask in Enterprise Sales Cycles
Sales cycles with enterprise prospects increasingly include a security review stage. The questions asked depend on the sophistication of the prospect's security team, but common themes:
Vendor data handling. If your product involves customer data, prospects will ask about the vendors you use to process that data. They want to know you have done due diligence on your own vendors and have appropriate contracts with them.
Third-party risk management process. Do you have one? Is it documented? Who owns it?
Incident notification. If one of your vendors has a security incident, how do you find out? How quickly do you notify affected customers?
Subprocessors. GDPR Article 28 requires a processor to obtain the controller's prior specific or general written authorization before engaging another processor and to inform the controller of intended changes under a general authorization. Contractual subprocessor-list obligations may go further; the GDPR does not state a universal public-list requirement in those terms.
How to Be Ready Before You Are Asked
The organizations that answer these questions confidently are the ones that have built their vendor compliance program before they needed it, not in response to a specific request.
The elements that need to be in place:
A vendor inventory that can be produced quickly, categorized by risk level and data access.
Documented compliance requirements for vendor types: what documents you collect, what coverage you require, what security controls you verify.
An audit trail showing that onboarding happened systematically: documents collected, verified, and stored with timestamps.
Expiration tracking that demonstrates ongoing monitoring instead of a single point-in-time snapshot.
Contracts with appropriate terms where law, risk assessment, or policy requires them for vendor data or system access.
The good news is that the evidence you need to answer these questions is the same evidence you generate through a systematic vendor compliance program. The audit readiness is a byproduct of doing the compliance work correctly.
An undocumented process is difficult for a reviewer to evaluate. Keep evidence proportionate to the risks and commitments you claim to meet. When buyers turn the same questions on your tooling, our security overview describes OnComply's controls.