INDEPENDENTLY VERIFIEDCREST member companyPenetration Testing · EMEA
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Cyber glossary
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Search almost 100 cyber terms—from CTEM and EASM to agentic testing, purple teaming and CREST—and get a useful plain-English answer.
Demystify the tech talk →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 readCyber Essentials: the complete guide for UK businesses
A practical guide to the five Cyber Essentials controls, certification routes, preparation, costs, evidence and annual renewal.
Read essential guide →ESSENTIAL · CYBER ESSENTIALS
CYBER ESSENTIALS · 7 min readWhat 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.
Read essential guide →ESSENTIAL · READINESS
READINESS · 8 min readHow to prepare for Cyber Essentials: a practical checklist
A straightforward Cyber Essentials checklist covering scope, software, access, updates, malware protection and assessment evidence.
Read essential guide →ESSENTIAL · CYBER ESSENTIALS PLUS
CYBER ESSENTIALS PLUS · 9 min readCyber 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.
Read essential guide →ESSENTIAL · FOUNDATION GUIDE
FOUNDATION GUIDE · 5 min readFirewall configuration best practices
Practical guidance for reducing unnecessary exposure and maintaining defensible firewall rules as part of a secure operating baseline.
Read essential guide →ESSENTIAL · COST GUIDE
COST GUIDE · 8 min readHow 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.
Read essential guide →ESSENTIAL · COMPARISON
COMPARISON · 8 min readCyber 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.
Read essential guide →Technical
Further technical information
Original Pentesys analysis for security, technology and assurance teams who need more detail.
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 readExternal 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.
Read essential guide →ESSENTIAL · EASM
EASM · 6 min readWhat is attack surface monitoring?
A plain-English introduction to continuously discovering and managing everything your organisation exposes online.
Read essential guide →ESSENTIAL · EXPOSURE
EXPOSURE · 7 min readHow exposed assets create cyber risk
Why reachability, exploitability and asset importance matter more than a severity number in isolation.
Read essential guide →ESSENTIAL · SHADOW IT
SHADOW IT · 6 min readWhy 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.
Read essential guide →ESSENTIAL · PARTNER GUIDANCE
PARTNER GUIDANCE · 12 min readVendor 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.
Read essential guide →Technical
Further technical information
Original Pentesys analysis for security, technology and assurance teams who need more detail.
REMEDIATION · PENTESYS POINT OF VIEW
Vulnerability remediation needs an operating model—not another spreadsheet
A Pentesys view of how ownership, context and verification turn identified exposure into measurable risk reduction.
Read the technical view →RISK PRIORITY · PENTESYS POINT OF VIEWStop treating vulnerability severity as vulnerability priority
Why reachability, credible attack paths and business consequence should determine the remediation queue.
Read the technical view →WEB RISK · PENTESYS POINT OF VIEWModern web risk lives between code, identity and cloud configuration
An evidence-led guide to connected web, API, identity and cloud risks, including authorised testing considerations for fintech and transaction-driven applications.
Read the technical view →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 readPenetration 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.
Read essential guide →ESSENTIAL · BUYER GUIDE
BUYER GUIDE · 9 min readHow to choose a penetration-testing provider
Compare penetration-testing providers on competence, accreditation, scope quality, safe delivery, reporting, data handling and remediation support.
Read essential guide →ESSENTIAL · PTaaS
PTaaS · 8 min readWhat is penetration testing?
What a professional penetration test examines, how it differs from scanning and what a useful outcome looks like.
Read essential guide →ESSENTIAL · ASSURANCE
ASSURANCE · 7 min readHow often should a business run a penetration test?
Why calendar-based testing is only a baseline—and which business changes should trigger additional validation.
Read essential guide →ESSENTIAL · BUYER GUIDE
BUYER GUIDE · 14 min readHow 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.
Read essential guide →ESSENTIAL · OPERATING MODEL
OPERATING MODEL · 9 min readIn-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.
Read essential guide →ESSENTIAL · GUIDE
GUIDE · 9 min readPenetration testing vs vulnerability scanning
A practical guide to automated breadth, authorised human investigation, evidence and choosing the right assurance for the security question.
Read essential guide →ESSENTIAL · POST-TEST
POST-TEST · 5 min readHow 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.
Read essential guide →ESSENTIAL · POST-TEST
POST-TEST · 10 min readWhich penetration-test findings should you fix first?
How to order confirmed penetration-test findings using validated exploitability, credible attack paths and business consequence.
Read essential guide →ESSENTIAL · AI TESTING
AI TESTING · 10 min readAI-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.
Read essential guide →ESSENTIAL · AGENTIC TESTING
AGENTIC TESTING · 11 min readWhat 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.
Read essential guide →ESSENTIAL · SCOPING
SCOPING · 9 min readDefining your external network penetration-testing scope
A practical guide to defining targets, objectives, exclusions and safe testing rules for an external network penetration test.
Read essential guide →ESSENTIAL · CLOUD TESTING
CLOUD TESTING · 11 min readCloud 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.
Read essential guide →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.
Read the technical view →ASSURANCE · PENTESYS POINT OF VIEWAnnual 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.
Read the technical view →VALIDATION · PENTESYS POINT OF VIEWA finding is not a risk decision until it has been validated
Why evidence, reproducibility and business context are essential before teams commit remediation effort.
Read the technical view →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 readRed 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.
Read essential guide →ESSENTIAL · RED TEAM
RED TEAM · 8 min readWhat is red teaming?
A plain-English guide to controlled adversary simulation and the questions a red team exercise answers.
Read essential guide →ESSENTIAL · COMPARISON
COMPARISON · 7 min readRed teaming vs penetration testing
How the scope, objectives and outputs differ—and when each form of testing provides the clearest answer.
Read essential guide →ESSENTIAL · MATURITY
MATURITY · 6 min readWhen does a company need red teaming?
The maturity signals that indicate your organisation is ready to gain value from an adversary simulation.
Read essential guide →ESSENTIAL · PURPLE TEAMING
PURPLE TEAMING · 9 min readPurple 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.
Read essential guide →Technical
Further technical information
Original Pentesys analysis for security, technology and assurance teams who need more detail.
INTERNAL RISK · PENTESYS POINT OF VIEW
Internal security is defined by attack paths, not network boundaries
How identity, privilege, lateral movement and detection shape the attack paths available after an attacker gains an initial foothold.
Read the technical view →METHODOLOGY · PENTESYS POINT OF VIEWA testing methodology should protect rigour without constraining curiosity
How disciplined scope, safe execution, structured coverage, evidence and creative human investigation combine in a defensible testing methodology.
Read the technical view →POST-TEST · PENTESYS POINT OF VIEWThe real value of a penetration test begins after delivery
The Pentesys route from technical findings to verified remediation and stronger organisational resilience.
Read the technical view →Not sure where to begin?
Turn the reading into a clear next step.
Take the two-minute security-priorities check to identify where visibility, validation or resilience may need attention without leaving this page.
Find my security priority →Assurance that joins up
Recognised expertise, built around your environment.
Pentesys combines independent assurance, qualified testers and practical integration with the systems your teams already use.
SECURITY TESTINGCREST approvedAssured company standards and delivery
Why CREST matters →
RESPONSIBLE AIAI Charter signatoryTransparent, trustworthy use of AI
Our assurance approach →
ORGANISATION-WIDECyber Essentials certifiedCurrent to 12 August 2027
View certificate ↗Explore the Pentesys product families
ONE PLATFORM. FOUR WAYS TO REDUCE EXPOSURE.
Start with the security outcome you need, then explore the Pentesys product family built around it.Get Cyber
Essentials ready
Find the gaps and organise your evidence for a smooth Cyber Essentials journey.
See and prioritise
your external exposure
AI-powered discovery shows what is exposed across your external attack surface.
Prove what can
be exploited
Expert-led testing confirms what matters and explains how to fix it.
Pressure-test your
real-world defences
Adversary simulations replicate real attacker behaviour to test your defences.