7 Key Insights on Technology Due Diligence

Technology due diligence is a structured review of a target’s technology, cyber security, compliance and operations carried out for M&A, investment or supplier onboarding. In the UK, technology due diligence should check exposure under UK GDPR and supply chain risks highlighted by the National Cyber Security Centre (NCSC, 2025).

It is essential to follow practical checklists such as the NCSC’s buyers’ guide (NCSC buyers’ guide) and consider supplier and contractual controls referenced in the Information Commissioner’s Office guidance on IT supplier relationships (ICO, UK GDPR supplier guidance). Good practice also reflects supply chain due diligence guidance such as the National Institute of Standards and Technology Special Publication 1326 (NIST SP 1326).

The review typically scopes architecture, source code, data handling, incident history and the team that operates the systems.

• What it is: A focused review of technology, cyber security, compliance and operations to surface risks that affect valuation, price or deal terms.
• When to run it: Do a light check at term sheet, a deeper audit after exclusivity and a pre-completion sweep for remediation.
• Typical scope: Architecture, source code, cyber controls, regulatory compliance and team skills with ranked remediation actions.
• At CyPro: We offer modular technology due diligence so buyers choose rapid or full audits depending on transaction materiality and risk.

🔍 What is technology due diligence and what does it cover?

Technology due diligence is a structured review of a target’s technology, security, compliance and operations to surface risks and opportunities for investment or supplier onboarding. The review covers infrastructure, software, security controls, data handling and the team supporting them.

Who commissions technology due diligence?

Buyers, investors, and procurement teams commonly commission technology due diligence when evaluating acquisitions, equity investments, or strategic suppliers. Private equity firms and corporate development teams use these reviews to validate valuations.

Procurement and legal teams use them to meet obligations under UK GDPR and third party risk policies.

Typical scope and deliverables

Technology due diligence typically inspects five areas:

1. Architecture and operational resilience,
2. Source code and development practices,
3. Cyber security controls,
4. Regulatory compliance,
5. The skills and processes of the IT team.

Deliverables usually include an executive risk summary, a technical findings report, remediation actions with priority and an estimate of effort to fix key issues.

Technical vs cyber security due diligence

Technical due diligence looks across product quality, scalability and technology debt. Cyber security due diligence drills into controls, incident history and attacker exposure.

Organisations commissioned for a deep security review may perform penetration testing, configuration reviews and evidence-based control testing.

In the UK, guidance from the NCSC and the National Institute of Standards and Technology (NIST) helps shape checklists and supplier questionnaires.

The NCSC Annual Review 2025 also highlights the importance of supply chain and acquisition checks for cyber resilience (NCSC, 2025).

At CyPro, we run modular technology due diligence engagements so clients can choose a light architecture review or a full security audit depending on transaction materiality. Our Due Diligence as a Service shortens response times for recurring supplier checks during growth or deal activity.

⏱️ When should you run technology due diligence in a deal?

Run technology due diligence when technology, security, or regulation could change price, deal structure, or post‑completion liability.

At CyPro, we recommend an early light‑touch check at pre‑term sheet to spot deal breakers. Perform a detailed technical and security audit during exclusivity, and a short pre‑completion sweep to confirm remediation and recovery assumptions.

When a faster or deeper review is needed

Evidence of prior incidents, a large regulated data footprint under UK GDPR, or complex third‑party supply chains mean start earlier and go deeper.

Industry reporting shows exploitation of vulnerabilities increased year on year in 2025. This makes early detection of unmanaged exposures more important than ever (Verizon, 2025).

Typical deal-stage checklist

Use this simple checklist to match scope to tempo. For competitive auctions, pick a rapid, evidence‑led review.

For strategic purchases, plan two rounds of assessment with enough time for remediation.

Deal stage	Focus	Deliverable
Pre‑term sheet	Ownership, major third‑party dependencies, recent incidents	One‑page risk summary, red flags list
Exclusivity / due diligence	Architecture, code quality, security posture, compliance	Detailed technical report, remediation plan, estimated costs
Pre‑completion	Confirm fixes, backup and recovery tests, contract risk	Final attestation, updated RTO/RPO, acceptance checklist
Post‑completion integration	Monitoring, patching, access control harmonisation	Integration plan, recommended monitoring and MDR handover

Scope your vendor asks to the deal stage. Request an architecture diagram and incident log early.

Run targeted code review and penetration testing mid‑deal, and insist on recovery verification before completion.

⚖️ Can technology due diligence scale for portfolios and rapid deals?

Yes, technology due diligence can scale across many targets and fast deal cycles by standardising evidence requests, automating low‑risk checks and triaging targets into light, medium or deep reviews.

Standardise checklists and evidence requests

Start with a single, risk‑based checklist that maps to standards such as ISO 27001 (ISO/IEC 27001), the National Cyber Security Centre (NCSC) buyer guidance, and Data Protection Act obligations under UK GDPR. Standard templates let you compare controls across targets quickly and reduce repeated questions. For recurring supplier checks we recommend a short automated questionnaire to confirm basics and flag missing evidence, then escalate only the riskiest targets.

Automation, platforms and where they help

Automation compresses cycles by handling low-value evidence and producing machine‑readable answers for things like patching cadence, MFA adoption and open ports. Use automation for initial screening and for repeated supplier programmes, but reserve human review for architecture, code quality and bespoke integrations. IBM’s 2025 threat analysis shows attackers increasingly exploit credentials and subtle misconfigurations, which means automation must be paired with targeted technical inspection rather than relied on alone (IBM, 2025).

Where lightweight templates are enough and where deep dives remain necessary

Light reviews suit small targets with standard SaaS stacks where third‑party certifications exist. Deep-dive bespoke reviews are necessary for targets with custom codebases, essential customer data or complex integrations. The Information Commissioner’s Office provides supplier relationship guidance that helps decide when to escalate to a full audit (ICO).

In practice, we combine platform screening with selective technical testing and an attack surface assessment to scale securely. For programmes that need both speed and depth, consider our attack surface assessment as the escalation step for medium and high risk targets.

✅ What should a practical technical and cyber checklist include?

The checklist should be a tight, evidence-led list covering architecture diagrams, dependency inventories, CI/CD pipelines, vulnerability backlogs and recovery plans, answering the core question for buyers and investors immediately.

Architecture and dependencies

Start with an up-to-date architecture diagram, service inventory and a dependency list that shows third parties, cloud services and data flows. Include versions, hosting regions and any single points of failure. For mergers or acquisitions, this part of technology due diligence quickly shows hidden operational risk and likely integration effort.

Code, build and deployment

Document the CI/CD pipeline, source control ownership, branch protection, and automated test coverage. Note open source components and the process for handling Common Vulnerabilities and Exposures (CVEs). A simple evidence pack of build logs and pipeline policies speeds technical reviews in the deal process and reduces rework.

Security controls and monitoring

List authentication methods, identity and access management (IAM) roles, multifactor authentication and session timeout policies. Include endpoint detection, logging retention, and where EDR or XDR is deployed. For detection and incident response, provide runbooks, on-call rotas and evidence of recent tabletop exercises.

Patching, vulnerabilities and technical debt

Provide a backlog of unfixed vulnerabilities, the patching cadence and the owners for each class of asset. Prioritise by exposure and exploitability rather than raw counts. Use an attack surface assessment to validate externally facing risks and to confirm which items are already being actively exploited by threat actors (Mandiant).

Resilience, backups and recovery

Show backup scope, recovery point objectives and recovery time objectives, and the IT Disaster Recovery Plan test history. Evidence of recent restore tests is often decisive for underwriting and operational teams. The National Cyber Security Centre’s buyer guidance gives examples of useful evidence to request from vendors (National Cyber Security Centre).

At CyPro, we treat technology due diligence as a staged programme: Quick screening, targeted testing and escalation where risk demands. That keeps reviews fast while ensuring the buyer sees clear, verifiable evidence of security, compliance and resilience.

🧰 How do we run technical due diligence: Methodology and tools?

We run technical due diligence in stages: Scoping, evidence collection, technical testing, stakeholder interviews and formal reporting, using automated scans plus manual review to produce a clear risk picture. Our process balances speed with depth so buyers get verifiable evidence fast.

Phases: What happens and why

Scoping sets the review boundaries and success criteria, evidence collection gathers architecture diagrams, access controls and CI/CD pipelines, technical testing exercises software composition analysis (SCA), vulnerability scanning and targeted penetration testing, and interviews validate operational practices. These phases ensure the technology due diligence output is actionable for legal teams, investors and IT teams.

Tools and techniques we commonly use

We combine SCA tools and authenticated vulnerability scanners with manual code review and threat modelling. Automated tooling finds known dependencies and common misconfigurations while manual testing identifies logic flaws and insecure design. For scale, we use continuous evidence collection tied to source control to reduce repeat work and speed conclusions.

Combining automated scans with manual review and red teaming

Automated scans give breadth, manual review gives depth and red teaming tests detection and response. Use cases in commercial M&A work often require an escalation path: Fast screening then an Red Teaming engagement where necessary, or an MDR escalation to prove detection capability with live telemetry. That escalation model reduces vendor churn and answers buyer questions quickly.

💷 How do you translate findings into deal risk and price adjustments?

Convert each technical finding into three priced outputs: A cost-to-fix, a likelihood-adjusted loss and a regulatory exposure number, then map those to contractual levers such as holdbacks, escrow or indemnities. This gives negotiators clear, priced choices.

Quantify the tech risk

Start with a pragmatic cost-to-fix that includes developer time, testing, patch deployment and verification. Estimate the probability of exploitation using evidence from scans, logs and access controls. Use sector guidance to weight exploitability where relevant; for example, the European Union Agency for Cybersecurity (ENISA, 2025) documents national priorities that affect how regulators and attackers focus on certain weaknesses.

Build remediation budgets and timelines

Next, produce a remediation budget and realistic timeline, with milestone testing and rollback plans. Convert timelines into business-impact days and estimated lost revenue. Where controls affect data protection, reference Information Commissioner Office resources to justify potential regulatory exposure when personal data is involved (ICO). Package each item as a priced line so finance and legal can see the numbers without technical translation.

Contract levers and insurer view

Finally, propose three commercial outcomes:

1. Seller remediation before close with proof
2. A holdback or escrow sized to the likelihood-adjusted loss
3. Enhanced indemnities limited to named findings.

Presenting these as priced options helps insurers and underwriters assess exposure quickly. In our experience, working-priced scenarios from technology due diligence reduce negotiation friction and focus legal efforts on the true residual risk. We often pair this with our Due Diligence as a Service to speed evidence collection and supply the verifiable proof that lawyers and underwriters need.

🔁 What happens after the deal: Remediation, monitoring and assurance?

At CyPro, we convert technology due diligence findings into a practical, timebound post-completion plan that a buyer can enforce and verify.

Prioritised remediation and evidence gates

Prioritised remediation should target the highest-likelihood and highest-impact issues first. Clearly define owners, deadlines, and evidence requirements.

How to verify fixes and when to retest

Retests should follow a risk-based cadence: Low-risk items can be self-attested by the seller and spot-checked by the buyer, while medium and high-risk findings must be retested by an independent assessor and results retained in an auditable trail. We map retest timing and acceptance criteria to published guidance from the National Cyber Security Centre (National Cyber Security Centre, 2025) and to the NIST supply chain due diligence quick start (NIST SP 1326, 2025), so gates are defensible to internal audit and external advisers.

Assurance options: Monitoring, certification and targeted testing

Buyers choose assurance based on residual risk and operational appetite. For continuous detection we typically recommend Managed Detection and Response, which provides 24/7 monitoring and incident handling. For control assurance that supports sales or regulatory confidence we recommend an ISO 27001 programme to produce documented policies and audit evidence. For high-uncertainty assets we recommend a focused red team or adversary simulation to confirm whether fixes hold up under attack.

At CyPro, we usually scope the initial retest as part of post-deal work, then hand verified evidence into an ongoing MDR contract or an ISO 27001 roadmap so buyers inherit demonstrable, verifiable controls rather than informal assurances. See our Managed Detection and Response service for monitoring options and our ISO 27001 service for certification roadmaps (Managed Detection and Response (MDR), ISO 27001).

Practical checklist for transaction teams

Action	Who	Evidence	Timing
Prioritise findings	Buyer security lead	Risk register with RAG ratings	Within 5 working days
Agree retest gates	Buyer legal and technical	Signed retest criteria and scope	Pre-completion
Perform independent retest	Third-party assessor	Retest report and artefacts	Before phased fund release
Put monitoring in place	Buyer operations	MDR onboarding reports	0-30 days post-completion

Clear evidence gates, independent retesting and a handover into monitoring or certification reduce the chance that residual issues reappear after completion. Buyers who follow documented, source-linked retest plans are better placed to resolve disputed findings and to meet audit or regulator queries.

❓ Frequently asked questions