Pen Testing Steps: A Complete 7 Phase Guide to Penetration Testing

Confidence in your penetration testing programme is essential, whether it’s for auditors asking about your ISO 27001 alignment, boards demanding assurance, or looming compliance frameworks such as PCI-DSS, DORA or NIS2.

To be sure that your penetration testing is up to scratch, it’s important to understand what really happens during a penetration test, how each of the pen testing steps maps to and mitigates business risk, and how to choose a reliable pen testing partner that will deliver meaningful results without disrupting your operations.

In this guide, we’ll walk you through the seven critical phases of penetration testing, explaining what goes into each step in plain language, showing how they build on each other, and highlighting exactly what you should expect from your penetration testing provider.

Understanding the steps of a penetration test will help you to commission one confidently, interpret the findings, and maximise the value for your business.

Key Takeaways

• Pen testing steps provide a structured approach to penetration testing, helping you to avoid surprises and effectively plan remediation and reporting.
• The seven phases of a penetration test simulate real attacker behaviour, assess business impact, and verify remediation once fixes have been applied.
• Not all providers are equal: choose one that aligns with your geographical market standards, holds recognised accreditations (CREST/CHECK), and understands your industry.
• Understanding the steps of a penetration test gives you clarity, control, and better ROI from your security investments.
• Tailor the process according to your environment (cloud, web-apps, hybrid) and ensure it meets your regulatory requirements; one size does not fit all.
• Avoid common mistakes such as an unclear scope, skipping post-test verification, or relying purely on automated tools.

What is a Penetration Test and Why Does it Matter

A penetration test (often shortened to pen test) is a controlled, authorised cyberattack on your systems, networks or applications, with the purpose of identifying vulnerabilities before a real hacker finds them and causes real damage to your business.

It goes beyond automated vulnerability scanning by combining manual techniques, attacker-style thinking, and business logic to simulate the real actions of a hacker and provide meaningful results.

Unlike a vulnerability scan, which only identifies your weaknesses against already well-known issues and attack vectors, a penetration test actively exploits those weaknesses to demonstrate what an attacker could achieve should they successfully infiltrate your systems.

A pen test is a step-by-step adversarial simulation that produces credible evidence of risk, rather than a long list of possible issues.

Penetration testing covers multiple test types: external (internet-facing infrastructure), internal (inside your network perimeter), web application, mobile application, cloud configurations, and will test APIs, IoT/OT and any other infrastructure within your business that could be seen as a weak point by attackers.

Each type of penetration test has its own nuances, but they all follow a consistent lifecycle process of preparation, execution and review.

Penetration testing is essential for several reasons:

• It helps you to meet compliance requirements and information security framework recommendations, such as ISO 27001 (asserting that you test controls), PCI-DSS (requires annual or change-based pen testing), and emerging regulations such as DORA (digital operational resilience) and NIS2.
• It provides assurance to stakeholders, including your board, auditors, and regulators, that your defences are not just documented, but are effective under real world attack conditions.
• It enables you to align technical findings with business operations, so remediation becomes purposeful rather than a tick box exercise.
• It helps you prioritise and act on the vulnerabilities that matter most to your business, rather than chasing non-critical noise.

For these reasons, choosing your pen test provider is a strategic decision. Your provider isn’t just a vendor; they should be your partner as you improve your cyber security.

In the next section, we’ll explore the seven key phases of a penetration test, setting out what you should expect to see at each step. These phases are governed by accreditations such as CREST and CHECK, which set out strict rules for best practice pen testing engagements and rigorously assess providers against these standards before awarding accreditation.

The 7 Steps of a Penetration Test

Penetration testing is best viewed as a structured, repeatable cycle rather than a one-off effort. At DigitalXRAID, we follow methodologies aligned with CREST and CHECK standards, combining a structured process with real world attack simulation, tailored to your business’s industry and needs. This ensures that each engagement is comprehensive, auditable, and relevant to your specific risk profile.

Here are the seven pen testing steps that we follow, and that you should expect when engaging any partner to conduct a penetration test for your cyber security:

1. Scoping and Pre-Engagement

We work with you to define clear objectives, rules of engagement, and any legal or regulatory requirements you may need to adhere to.

Our scoping process is thorough and customised to your industry, compliance obligations, and risk appetite, ensuring that the test is both relevant and efficient.

Key steps in phase 1:

• Define the pen test scope (assets, networks, applications in/out of scope)
• Establish business objectives, including defining ‘can we access sensitive data, simulate insider threat, assess cloud misconfigurations, etc?’
• Determine test style: black box (no knowledge), grey box (partial knowledge), white box (full knowledge), or even Threat-Led Pen Testing or Red Teaming.
• Agree on a timeframe, exclusions, safe-testing windows, and clear escalation protocols. For example, black/white/grey box distinctions matter significantly.
• Contractual/authorisation work (rules of engagement, non-disclosure, insurance, liability).
• Understand and communicate compliance requirements: ensure the testing covers your regulatory needs (PCI-DSS, DORA, NIS2) and supports your audit evidence.
• Define success criteria and reporting requirements (both technical and executive).

Getting this first phase right really matters; a poorly scoped test can miss key assets, lead to uncontrolled disruption, or produce irrelevant findings.

Advice from the Centre for the Protection of National Infrastructure (CPNI) and CREST highlights that preparation and governance are foundational stages of penetration testing.

2. Intelligence Gathering and Reconnaissance

Once the scope is agreed, your penetration testing provider now needs to gather as much information as possible about the target environment and how a hacker might begin an attack. Reconnaissance is where your testers build an attacker’s view of your organisation.

The goal is to understand what is exposed, what technologies you run, and where weaknesses might exist, before any actual exploitation begins.

Key aspects of this stage include:

• Passive reconnaissance: OSINT (open-source intelligence) such as domain names, DNS records, company job ads, public infrastructure, and archive data.
• Active reconnaissance: Including port scanning, banner grabbing, and service enumeration. The provider should utilise scanning tools approved by CREST for use, such as Nessus, Acunetix, Burp Suite, and Qualys.
• Mapping the attack surface: identifying exposed services, internet-facing infrastructure, cloud misconfigurations, and third-party dependencies.
• Establishing baseline attacker view: what an external or internal attacker could discover about you before launching deeper exploitation.

In this phase, you want your provider to clearly outline the intelligence methods they use, explain to you what they found, and how that maps to your business and risk. Many methodologies, for example, OSSTMM and PTES, emphasise intelligence gathering as a fundamental early stage.

Breast Cancer Now Infrastructure Pen Test Information Gathering

Breast Cancer Now engaged DigitalXRAID to perform regular internal and external infrastructure testing, with additional assessments on selected web applications.

During the reconnaissance stage, our consultants:

• Fingerprinted internet-facing assets to identify open ports and potential access points, then used active scanning techniques to validate what was truly exposed.
• Collected version information on software and hardware in use to spot outdated components that could widen the attack surface.
• Performed passive monitoring within internal environments to understand normal network behaviour and identify services that could be targeted later.
• Investigated identity authentication and authorisation flows to evaluate whether common misconfigurations or weak controls might allow a bypass in subsequent phases.
• Assessed encryption for data in transit, checking SSL and TLS configurations for weaknesses, and verifying that sensitive information was transmitted securely.

This structured intelligence phase meant the later analysis and attack simulation were tightly focused on the areas that mattered most.

3. Vulnerability Identification and Risk Analysis

With the attack surface mapped, the next step is to identify your real world vulnerabilities and evaluate their likely impact on your organisation if successfully breached.

Key activities for phase 3:

• Automated scanning combined with expert manual review: Tools such as Nessus and others approved by CREST are used in this stage.
• Manual verification to filter false positives: The tester must assess whether the found vulnerabilities are exploitable in your specific context.
• Applying risk frameworks: Use of CVSS (Common Vulnerability Scoring System) to rate technical severity, but importantly, tying that severity to your business context by understanding what data is at risk, and what systems matter to your operations.
• Prioritising vulnerabilities: This should be based on exploitability and impact.

For senior stakeholders, this phase is critical. You need to know more than just ‘we found 1,000 vulnerabilities’; more importantly, you need to understand ‘these three issues could allow an attacker to reach your most sensitive data in under 35 minutes’.

4. Exploitation and Lateral Movement

Now the real action begins; the tester will try to exploit a vulnerability to demonstrate what an attacker could achieve if it’s successfully breached.

The key focus in step 4 is to:

• Exploit validated vulnerabilities as permitted in scope and gain entry to systems.
• Escalate privileges, moving laterally within networks, and accessing sensitive systems.
• Chain vulnerabilities where possible. For example, exploit an external host to pivot into your internal network, to eventually access business-critical data.
• Simulate attacker behaviour, not just automated script execution.

This step is where a well-run pen testing engagement starts to deliver you real business value. It bridges the gap between understanding that vulnerabilities exist and proving how an attacker can get in.

5. Post-Exploitation and Privilege Escalation

With initial access established, the tester explores what an attacker is able to achieve. This phase centres on persistence and impact.

Activities for exploitation and escalation can include:

• Evaluating the extent of access: Has the tester been able to access sensitive data? Take control of critical systems? Modify infrastructure?
• Persistence: Have the team been able to set up access to return to later, installing backdoors (where authorised in the scope) or simulate the ability to do so to conduct a robust and fully comprehensive test?
• Lateral movement: Were the testers able to move across different segments, services, and sub-nets in your infrastructure to demonstrate the potential reach and damage an attacker could make?
• Cleanup planning: The testers should ensure that the environment is restored to its original state after testing.

By exploring this pen testing step, you gain insight not only into your vulnerabilities but how a breach could unfold in your environment. This is vital intelligence for CISOs and IT Directors who need to manage business risk.

6. Reporting and Remediation Planning

Having executed the test, the next phase is about presenting the findings in a way that drives action.

You should expect the following deliverables:

• A technical report that lists findings, evidence of exploitation, impact analysis, and severity ratings (CVSS plus business context).
• An executive summary that translates technical results into business risk in understandable terms.
• Prioritised remediation recommendations, which shouldn’t simply be “patch this” but “patch this within 30 days because business risk is high in context”.
• Risk scoring that is aligned with your environment, not generic. DigitalXRAID adds an industry-specific business risk score for each finding, so you can present to your board with confidence and concentrate on the highest priority areas for remediation.
• Meeting your compliance obligations, for example, the NCSC guidance states that you should document the severity and evidence of exploitation.

The quality and clarity of testing reports often distinguish providers. Technical detail is necessary, but without business context, you and your board can’t act.

We often see organisations that return with the same vulnerabilities for months at a time because they don’t have visibility of remediation efforts, and things get missed. An essential part of penetration testing is the remediation to fix any issues that have been identified. One way that DigitalXRAID gives customers visibility, tracking, and reporting on vulnerability remediation is through the OrbitalX security portal.

7. Retesting and Continuous Security Improvement

A penetration test shouldn’t be a one-and-done exercise. After remediation, the retesting phase ensures that the loop is closed.

Because pen testing only shows a snapshot in time of vulnerabilities, but your infrastructure is going through constant updates and patches, you should maintain a regular cadence of testing to stay on top of your current security risks.

Key items for the final stage:

• Verification testing to confirm that any identified vulnerabilities have been remediated and no regression has been introduced.
• Conduct a lessons learned workshop internally or with your provider to discuss what went well, what didn’t, and how to incorporate findings into your security assurance framework (such as needing to expand security measures to include a Security Operations Centre (SOC) for 24/7 monitoring).
• Incorporation of findings into your wider security strategy: not just “we fixed this bug”, but “we improved our process so that next time we don’t keep finding the same issue”.
• Continuous improvement: many providers stop at the report, but you need a partner who helps you to embed the changes and track metrics over time. CREST best practice advice emphasises that follow-up activities are a key part of a mature pen testing programme.

By viewing penetration testing as a cycle, not a one-off event, you extract maximum value, reduce repeat findings, improve your security posture, and demonstrate ongoing maturity to your stakeholders.

Tailoring the Penetration Test Steps for Different Testing Scenarios

Different environments demand different approaches. The steps and phases above remain valid for all tests, but the details should vary depending on your scenario. For example:

• Cloud / Hybrid infrastructure: The scope needs to include cloud-native services. IAM roles, misconfigurations in discovery, and lateral movement may look different.
• Web application / APIs: Testing focuses both on technical vulnerabilities (OWASP Top 10, API misuse) and business logic flaws. Methods such as white box (code review) may be appropriate.
• Internal network / OT / IoT: They are often more complex segments and higher risk, so lateral movement is key. Penetration testing phases may need deeper exploration of persistence and pivoting.
• Regulated sectors / critical infrastructure: Additional regulatory overlay is needed, for example, financial firms under DORA, which means you may need threat-intelligence led pen testing, longer timeframes, and high assurance credentials.
• Time / budget constraints: Sometimes you may opt for targeted testing, for example, just one business unit or application, rather than full enterprise coverage. Make sure that your scope is clear and expectations are adjusted accordingly.

Always ensure that your provider discusses the environment specific risks with you and tailors their methodology to your business. Your provider should link any findings back to your key business functions and compliance obligations.

Common Mistakes, Pitfalls and Best Practices

Let’s talk about what often goes wrong and how to avoid it. You can use this as a checklist when commissioning or reviewing your next pen test to make sure you avoid these pitfalls.

Mistakes & Pitfalls

• Poor scoping: Leaving out critical assets, cloud services, or third-party dependencies leads to false comfort.
• Skipping post-test verification: Without retesting, you may think you’re secure, but vulnerabilities can persist.
• Over-reliance on automated scanning: Automated testing tools alone can’t replicate attacker logic, chaining, or business-logic exploitation. Research shows that many breaches exploit what automated scanning misses.
• Inadequate reporting: A long list of vulnerabilities without business impact or prioritisation leaves you with little value.
• Choosing providers solely on cost: You might get fast results, but you won’t get a full adversary simulation aligned with your risk profile if you opt for the cheapest service.
• Lack of governance and programme maturity: One-off tests, rather than testing as part of a broader assurance framework, weaken your security posture.

Best Practices

• Define clear business objectives for the penetration test: What do you want to achieve beyond “find vulnerabilities”?
• Engage stakeholders early: Your board, compliance, legal, and business units should understand the penetration test’s role and value.
• Choose an accredited provider (CREST, CHECK): Check that your provider has demonstrable experience and accreditations.
• Ensure reporting is meaningful: Ask specifically for business risk scoring, an executive summary, and remediation lifecycle tracking.
• Incorporate remediation into your wider programme: Assign actions, track progress, and integrate with your vulnerability management and managed SOC service to close the loop on risks.
• View pen testing as part of a perpetual improvement cycle: Test → remediate → test again.
• Tailor to scenarios: Web apps, cloud services, and internal networks all have unique risks. Make sure that your testing scope adapts accordingly.
• Budget for retesting and follow-up: Without this, you might simply revisit the same vulnerabilities again and again.

Use this checklist as part of your internal procurement process when engaging a new provider or reviewing an existing provider’s service.

Why DigitalXRAID’s Approach Stands Out

When you commission a provider to walk you through their pen testing steps, you need to look out for more than technical capability. You need strategic alignment, industry insight, and ongoing value for your business.

Here’s why DigitalXRAID is the strategic choice:

• Accreditation and rigorous standards: We hold CREST and CHECK certifications, demonstrating that our methodologies, personnel, and governance meet best practice benchmarks for pen testing in the UK public and private sectors.
• UK based, trusted partner: You’re working with a provider embedded in the UK regulatory environment, experienced with UK and EU compliance requirements, legal frameworks, and business models.
• Business-focused reporting: We deliver both detailed technical findings and executive-level business risk summaries, ensuring you can present to your board or auditors with confidence.
• Tailored methodology: Our approach to the pen testing steps and phases is customised to your business sector, risk appetite, compliance obligations, and organisational maturity.
• Lifecycle mindset: We don’t stop at the report; we offer remediation verification, tracking via the OrbitalX security portal, and embed lessons learned to ensure your security posture advances, instead of staying static.
• Minimal disruption, maximum value: We collaborate closely with your teams to agree safe times, pause criteria, rollback plans, and ensure business continuity while delivering real-world-mimicking testing.
• Transparent engagement: We walk you through each of the penetration testing steps, demystify technical jargon, align to your business language, and help you translate findings into action.

If you’re looking to shift from uncertainty to clarity in your cyber assurance, DigitalXRAID is ready to help you navigate the full pen testing lifecycle, from scoping to retesting, with expertise and strategic insight.

Ready to Take the Next Step in Penetration Testing?

You now understand the full lifecycle of pen testing, what to expect at each of the steps of a penetration test, and how to avoid common pitfalls.

You’re better equipped as an IT Director, CISO, or Compliance Manager to commission a provider, evaluate results, and drive meaningful remediation for your organisation.

If you’re ready to elevate your security assurance, talk to us or book a tailored scoping session. We’ll help you to define the right scope for your requirements, agree on the right style of testing (black/grey/white box), ensure compliance alignment where necessary, and deliver a business-centric outcome.

FAQs on Pen Testing Steps

How many phases are there in penetration testing?

Most providers use a 7 phase lifecycle: scoping, reconnaissance, vulnerability identification, exploitation, post-exploitation, reporting and retesting. Some group steps into 4–5 phases, but the activities are the same.

How long does each phase take?

The duration of each phase depends on your scope, complexity, and environment. A typical external infrastructure pen test might take 1–2 weeks of active testing, but a full programme including scoping, exploitation, reporting, and retesting can span 4–6 weeks or more. For complex environments (cloud, OT/IoT, critical infrastructure), this can extend further. Timing should be agreed in the scoping phase, and the provider should deliver a schedule.

What are the steps of penetration testing?

The standard seven steps are scoping, reconnaissance, vulnerability identification, exploitation, post-exploitation, reporting and retesting. Each phase builds evidence and drives remediation efforts.

Can certain systems be excluded from a pen test?

Yes, exclusions are common, and they should be agreed upon during the scoping phase. Critical systems that cannot tolerate any risk of disruption may be excluded or tested in isolation. However, excluding too much can undermine the value of the test, so scope carefully and ensure you’re not leaving high risk assets unchecked.

What deliverables should be included?

Key deliverables include a technical report (with findings, exploitation evidence, CVSS, and business risk scoring), an executive summary (for non-technical stakeholders), remediation recommendations with prioritisation, timelines, evidence of exploit paths, and optionally retest confirmation. A test programme may also include a lessons learned workshop and tracking dashboard.

Will testing disrupt operations?

When planned correctly, disruption is minimal. Leading providers will schedule safe windows, obtain authorisation, and agree on rollback procedures. The risk of business disruption is far higher if a real attacker exploits the same vulnerabilities. That said, you should always assess critical services and agree on acceptable levels of downtime plans during the scoping phase.

How often should you retest?

You should test annually as a minimum for most organisations, but retesting is recommended after any major change (new infrastructure, application deployment, cloud migration, etc.) and for high risk systems, testing should be quarterly or continuous. A maturity-based approach aligns with governance frameworks.

What is the difference between scanning and penetration testing?

Looking at vulnerability scanning vs pen testing, vulnerability scanning uses automated tools to identify potential weaknesses (open ports, missing patches, misconfigurations). A penetration test goes further, attempting to exploit vulnerabilities (within scope) to demonstrate what an attacker could achieve, providing proof of impact and validating controls. Scanning is useful and broad, but alone it can’t provide the depth or assurance that a penetration test offers.