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Cyber glossary

Lost in the acronyms?

Search almost 100 cyber terms—from CTEM and EASM to agentic testing, purple teaming and CREST—and get a useful plain-English answer.

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Foundation

Get Cyber Essentials Ready

Cyber Essentials can unlock contracts, strengthen supplier confidence and reduce common cyber risks. Foundation shows you what needs attention, gives your team clear remediation actions and prepares the evidence for a smoother assessment.

Base level

Essential guidance

Begin here for a clear, practical explanation without unnecessary jargon.

ESSENTIAL · COMPLETE GUIDE
COMPLETE GUIDE · 14 min read

Cyber Essentials: the complete guide for UK businesses

A practical guide to the five Cyber Essentials controls, certification routes, preparation, costs, evidence and annual renewal.

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ESSENTIAL · CYBER ESSENTIALS
CYBER ESSENTIALS · 7 min read

What is Cyber Essentials? A plain-English guide for UK businesses

What Cyber Essentials covers, why customers and tenders ask for it, and how the UK certification process works.

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ESSENTIAL · READINESS
READINESS · 8 min read

How to prepare for Cyber Essentials: a practical checklist

A straightforward Cyber Essentials checklist covering scope, software, access, updates, malware protection and assessment evidence.

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ESSENTIAL · CYBER ESSENTIALS PLUS
CYBER ESSENTIALS PLUS · 9 min read

Cyber Essentials Plus: what the technical assessment actually checks

A practical guide to the independent technical checks behind Cyber Essentials Plus—and how to prepare without confusing the assessment with a penetration test.

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ESSENTIAL · FOUNDATION GUIDE
FOUNDATION GUIDE · 5 min read

Firewall configuration best practices

Practical guidance for reducing unnecessary exposure and maintaining defensible firewall rules as part of a secure operating baseline.

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ESSENTIAL · COST GUIDE
COST GUIDE · 8 min read

How much does Cyber Essentials cost in the UK? Fees, preparation and hidden effort

The current certification fee, the work that sits around it and how to budget realistically for Cyber Essentials or Cyber Essentials Plus.

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ESSENTIAL · COMPARISON
COMPARISON · 8 min read

Cyber Essentials vs Cyber Essentials Plus: which certification does your organisation need?

How the two Cyber Essentials certification levels differ, when Plus is requested and how to choose a proportionate route.

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Technical

Further technical information

Original Pentesys analysis for security, technology and assurance teams who need more detail.

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Expose

See and Prioritise Your External Exposure

Your internet-facing estate changes every day. Expose continuously discovers exposed assets, leaked credentials and relevant threat activity—then turns that signal into a clear, prioritised view of what needs action.

Base level

Essential guidance

Begin here for a clear, practical explanation without unnecessary jargon.

ESSENTIAL · COMPLETE GUIDE
COMPLETE GUIDE · 15 min read

External attack surface management: how to find and reduce unknown exposure

How EASM discovers internet-facing assets, adds threat context, supports remediation and proves that external exposure is reducing.

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ESSENTIAL · EASM
EASM · 6 min read

What is attack surface monitoring?

A plain-English introduction to continuously discovering and managing everything your organisation exposes online.

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ESSENTIAL · EXPOSURE
EXPOSURE · 7 min read

How exposed assets create cyber risk

Why reachability, exploitability and asset importance matter more than a severity number in isolation.

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ESSENTIAL · SHADOW IT
SHADOW IT · 6 min read

Why forgotten domains and cloud assets are dangerous

How forgotten domains, temporary cloud services and unclear ownership create persistent external exposure—and what to do about it.

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ESSENTIAL · ASSET DISCOVERY
ASSET DISCOVERY · 10 min read

External attack surface discovery: how to find internet-facing assets you do not know about

A practical guide to discovering unknown internet-facing assets, validating ownership and turning an outside-in inventory into accountable action.

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ESSENTIAL · PARTNER GUIDANCE
PARTNER GUIDANCE · 12 min read

Vendor security assessments: a practical guide to third-party assurance

A practical guide for MSPs and security teams on supplier tiering, evidence collection, authorised external visibility and proportionate technical assurance.

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ESSENTIAL · BUYER GUIDE
BUYER GUIDE · 3 min read

Continuous vulnerability management from discovery to verified action

Understand the workflow, ownership and platform requirements behind an effective vulnerability-management programme.

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ESSENTIAL · RESOURCE HUB
RESOURCE HUB · 3 min read

Threat intelligence resources from signals to decisions

Connect threat reporting, leaked-data intelligence and external visibility to prioritisation, controlled investigation and practical action.

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ESSENTIAL · BUYER GUIDE
BUYER GUIDE · 3 min read

Cybersecurity due diligence for mergers and acquisitions

Combine authorised external evidence, management information and targeted assessment before and after a transaction.

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ESSENTIAL · BUYER GUIDE
BUYER GUIDE · 3 min read

Third-party security validation and testing boundaries

Evaluate supplier evidence and decide when authorised technical testing is justified, without confusing public visibility with permission.

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ESSENTIAL · BUYER GUIDE
BUYER GUIDE · 3 min read

AI security strategy for UK technology and security teams

Prioritise AI-related exposure, governance and assurance decisions without losing sight of established security controls.

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Explore the See and Prioritise Your External Exposure pillar →

Validate

Prove What Can Be Exploited

Validate combines vulnerability assessment, AI-enabled coverage and CREST-aligned human penetration testing. Your team sees what is genuinely exploitable, why it matters and whether the fix has been independently verified.

Base level

Essential guidance

Begin here for a clear, practical explanation without unnecessary jargon.

ESSENTIAL · COMPLETE GUIDE
COMPLETE GUIDE · 16 min read

Penetration testing: scope, process, costs and what happens after the report

A buyer's guide to penetration-test scope, methodology, provider selection, reporting, remediation, retesting and continuous assurance.

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ESSENTIAL · BUYER GUIDE
BUYER GUIDE · 9 min read

How to choose a penetration-testing provider

Compare penetration-testing providers on competence, accreditation, scope quality, safe delivery, reporting, data handling and remediation support.

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ESSENTIAL · API TESTING
API TESTING · 12 min read

How to assess API penetration-testing requirements

A practical guide to deciding which APIs need testing, what belongs in scope and what access, accounts and evidence testers need.

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ESSENTIAL · PTaaS
PTaaS · 8 min read

What is penetration testing?

What a professional penetration test examines, how it differs from scanning and what a useful outcome looks like.

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ESSENTIAL · ASSURANCE
ASSURANCE · 7 min read

How often should a business run a penetration test?

Why calendar-based testing is only a baseline—and which business changes should trigger additional validation.

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ESSENTIAL · BUYER GUIDE
BUYER GUIDE · 14 min read

How to scope and prepare for a penetration test without missing critical systems

A practical method for defining penetration-test scope and preparing assets, access, monitoring, approvals and rules of engagement.

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ESSENTIAL · OPERATING MODEL
OPERATING MODEL · 9 min read

In-house vs outsourced penetration testing: choosing the right operating model

Compare independence, specialist depth, continuity, capacity, cost and governance when deciding who should perform penetration testing.

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ESSENTIAL · GUIDE
GUIDE · 9 min read

Penetration testing vs vulnerability scanning

A practical guide to automated breadth, authorised human investigation, evidence and choosing the right assurance for the security question.

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ESSENTIAL · POST-TEST
POST-TEST · 5 min read

How to present penetration-test findings to the board

Turn validated technical findings into the business decisions, remediation oversight and residual-risk questions a board needs to address.

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ESSENTIAL · POST-TEST
POST-TEST · 10 min read

Which penetration-test findings should you fix first?

How to order confirmed penetration-test findings using validated exploitability, credible attack paths and business consequence.

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ESSENTIAL · AI TESTING
AI TESTING · 10 min read

AI-assisted penetration testing: where automation ends and expert judgement begins

How AI-assisted penetration testing expands repeatable coverage without confusing automated output with independently validated security evidence.

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ESSENTIAL · AGENTIC TESTING
AGENTIC TESTING · 11 min read

What is agentic security testing? Autonomous testing with human-controlled guardrails

A practical explanation of how AI agents can plan, execute and adapt penetration testing while scope, safety, evidence and human validation remain controlled.

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ESSENTIAL · SCOPING
SCOPING · 9 min read

Defining your external network penetration-testing scope

A practical guide to defining targets, objectives, exclusions and safe testing rules for an external network penetration test.

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ESSENTIAL · CLOUD TESTING
CLOUD TESTING · 11 min read

Cloud penetration testing UK: a buyer's guide to cloud security assurance

What UK buyers should scope, authorise and expect when commissioning penetration testing across AWS, Azure or Google Cloud.

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ESSENTIAL · BUYER GUIDE
BUYER GUIDE · 3 min read

Penetration testing for ISO 27001 assurance

Connect risk-led testing, remediation evidence and audit preparation within an information security management system.

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ESSENTIAL · BUYER GUIDE
BUYER GUIDE · 3 min read

Mobile application penetration testing scope and evidence

Scope iOS and Android clients alongside their APIs, identities, data handling and supporting services.

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ESSENTIAL · BUYER GUIDE
BUYER GUIDE · 3 min read

Infrastructure penetration testing cost and scoping

Build comparable infrastructure proposals around internal and external boundaries, identities, constraints and useful deliverables.

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ESSENTIAL · BUYER GUIDE
BUYER GUIDE · 3 min read

Web application penetration testing cost and proposal inputs

Compare application-testing quotations using roles, workflows, endpoints, complexity, environment access and retest assumptions.

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ESSENTIAL · BUYER GUIDE
BUYER GUIDE · 3 min read

E-commerce penetration testing across checkout and customer accounts

Scope storefronts, checkout, customer data, payment integrations and order-management logic as one connected service.

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ESSENTIAL · BUYER GUIDE
BUYER GUIDE · 3 min read

Sharing penetration test results with customers

Give customers useful assurance while protecting technical detail, third-party information and the meaning of the original scope.

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ESSENTIAL · BUYER GUIDE
BUYER GUIDE · 3 min read

Building a business case for penetration testing and red teaming

Tie testing spend to a decision, realistic scope, remediation capacity and evidence rather than unsupported return-on-investment claims.

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ESSENTIAL · BUYER GUIDE
BUYER GUIDE · 3 min read

Bug bounty programmes versus penetration testing

Compare ongoing vulnerability reporting with a defined assessment, including incentives, coverage, permission and remediation workflow.

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ESSENTIAL · BUYER GUIDE
BUYER GUIDE · 3 min read

PCI DSS penetration testing scope and evidence

Plan payment-security testing around the cardholder-data boundary, segmentation, change and assessor-ready evidence.

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ESSENTIAL · BUYER GUIDE
BUYER GUIDE · 3 min read

SOC 2 and penetration testing evidence

Prepare scoped technical-testing evidence for a SOC 2 assurance process without confusing the assessment with the auditor’s report.

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ESSENTIAL · BUYER GUIDE
BUYER GUIDE · 3 min read

GDPR security testing and Article 32 assurance

Use a risk-based security assessment to support personal-data protection, with clear scope, handling and remediation evidence.

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ESSENTIAL · BUYER GUIDE
BUYER GUIDE · 3 min read

Protecting special category data in applications and services

Identify sensitive information paths and assess access, handling and evidence without treating a technical test as a lawful-basis decision.

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ESSENTIAL · BUYER GUIDE
BUYER GUIDE · 3 min read

Continuous penetration testing and change-led assurance

Define the schedule, change triggers, authorised response and human involvement behind recurring testing.

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ESSENTIAL · BUYER GUIDE
BUYER GUIDE · 3 min read

Fintech application security assessment checklist

Scope financial workflows, identities, APIs, third-party dependencies and operational safeguards before an application assessment.

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ESSENTIAL · BUYER GUIDE
BUYER GUIDE · 3 min read

Black box grey box and white box penetration testing

Choose information and access assumptions that match the assessment objective, available effort and important risk questions.

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ESSENTIAL · BUYER GUIDE
BUYER GUIDE · 3 min read

Healthcare security assessment scope and procurement

Plan proportionate assurance around patient information, connected workflows, suppliers and operational safety.

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ESSENTIAL · QUESTIONS ANSWERED
QUESTIONS ANSWERED · 3 min read

Security testing questions on scope delivery and follow-up

Answers to common questions about authorisation, testing models, prices, supplier boundaries, reports and remediation.

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Technical

Further technical information

Original Pentesys analysis for security, technology and assurance teams who need more detail.

PEN TESTING · PENTESYS POINT OF VIEW

Modern penetration testing should create decisions, not just findings

The Pentesys position on scoping, human expertise and evidence-led outcomes from a modern penetration test.

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ASSURANCE · PENTESYS POINT OF VIEW

Annual testing is a snapshot in a continuously changing estate

How continuous exposure visibility and event-led expert validation create a current, defensible security-assurance programme.

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VALIDATION · PENTESYS POINT OF VIEW

A finding is not a risk decision until it has been validated

Why evidence, reproducibility and business context are essential before teams commit remediation effort.

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ENGINEERING · PENTESYS POINT OF VIEW

IDOR remediation and object authorisation

Fix object-level access failures and verify tenant and role boundaries across related operations.

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ENGINEERING · PENTESYS POINT OF VIEW

SQL injection prevention and remediation verification

Keep untrusted values separate from query structure and verify the actual database-access paths.

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ENGINEERING · PENTESYS POINT OF VIEW

XSS prevention across rendering and content workflows

Choose controls for the actual browser output context and check stored client-side and rich-content paths.

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ENGINEERING · PENTESYS POINT OF VIEW

OWASP Top 10 2025 for development teams

Translate the current awareness list into engineering priorities and a testable application-specific plan.

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Explore the Prove What Can Be Exploited pillar →

Adversary

Pressure-Test Your Real-World Defences

Adversary safely simulates credible attacker behaviour to test whether your people, processes and technology can detect, contain and respond before a realistic objective is reached.

Base level

Essential guidance

Begin here for a clear, practical explanation without unnecessary jargon.

ESSENTIAL · COMPLETE GUIDE
COMPLETE GUIDE · 16 min read

Red teaming explained: when your organisation is ready and what an exercise proves

How red, purple and threat-led exercises differ, when to use them, how they are governed and how to measure defensive improvement.

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ESSENTIAL · RED TEAM
RED TEAM · 8 min read

What is red teaming?

A plain-English guide to controlled adversary simulation and the questions a red team exercise answers.

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ESSENTIAL · COMPARISON
COMPARISON · 7 min read

Red teaming vs penetration testing

How the scope, objectives and outputs differ—and when each form of testing provides the clearest answer.

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ESSENTIAL · MATURITY
MATURITY · 6 min read

When does a company need red teaming?

The maturity signals that indicate your organisation is ready to gain value from an adversary simulation.

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ESSENTIAL · PURPLE TEAMING
PURPLE TEAMING · 9 min read

Purple teaming explained: turn attack techniques into measurable detection improvement

How a collaborative purple team exercise helps attackers and defenders measure coverage, tune detections and build a verified improvement backlog.

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ESSENTIAL · BUYER GUIDE
BUYER GUIDE · 3 min read

Five myths about social engineering security testing

Plan useful, authorised social-engineering exercises without confusing click rates, blame or unrestricted realism with assurance.

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ESSENTIAL · RESOURCE HUB
RESOURCE HUB · 3 min read

Red teaming resources for planning testing and follow-through

A practical route through exercise selection, objectives, safe delivery, detection evidence and improvement planning.

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ESSENTIAL · BUYER GUIDE
BUYER GUIDE · 3 min read

Threat-led penetration testing and TLPT planning

Use relevant threat scenarios, explicit governance and useful defensive evidence while distinguishing formal framework requirements.

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Explore the Pressure-Test Your Real-World Defences pillar →

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Pentesys combines independent assurance, qualified testers and practical integration with the systems your teams already use.

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ONE PLATFORM. FOUR WAYS TO REDUCE EXPOSURE.

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