Penetration testing is no stunt – it’s a routine part of engineering and operations. It reveals real attack paths before release, validates assumptions, closes issues, and keeps delivery moving. Sounds simple. In practice the details matter: the test method, how findings are explained, whether retests are included, and the clarity of remediation steps.
Picking a provider is critical. Look for accreditations and practitioner depth, the balance of manual techniques, the strength of evidence in reports, data handling practices, and communication. The test should fit your way of working, not derail it. This article reviews established providers across Europe so you can compare approaches and choose what matches your style, scale, and goals.
1. A-Listware
We run security work as an engineering routine, not a side show. Penetration testing sits in the core of that routine, alongside secure development and code review. Scopes range from web and mobile to APIs, cloud surfaces, and classic network layers. We map real attack paths, prove impact, and hand back fixes that fit delivery cadence. Our team delivers penetration testing in the Europe and serves customers in the region, folding results into existing release cycles without drama.
During execution we mix manual exploration with tooling. Short bursts, then calm notes. We pivot through auth flows, broken access controls, injection edges, insecure deserialization, cloud misconfigurations, the usual suspects and the odd ones too. If an exploit needs proof, we record a clean PoC or a short video. If a fix is obvious, we write it down in plain words, not riddles. For teams that live in Jira or Azure DevOps, we push tickets with all the context so work keeps moving.
Afterwards we retest. Small but important step. The goal is closure, not just a report. We also run a quick debrief to share patterns we noticed across apps or environments. That feeds the next sprint, and the one after. Europe based clients use this loop as a rhythm around releases, audits, and change windows. It stays practical. It travels well between teams.
Key Highlights:
- Manual deep dives paired with smart tooling to cut noise, keep signal high
- Clear evidence trails that link each finding to a reproducible path and fix
- Coverage that spans apps, APIs, cloud, and networks for a joined view of risk
- Work rhythms aligned to European clients and delivery teams, not one-off reports
Services:
- Application and API penetration tests with exploit validation and remediation guidance
- Network and cloud attack surface assessments with targeted proof of impact
- Secure code review to surface design flaws scanners miss
- Adversary style exercises when leadership needs a goal driven check of defenses
Contact Information:
- Website: a-listware.com
- Email: info@a-listware.com
- Facebook: www.facebook.com/alistware
- LinkedIn: www.linkedin.com/company/a-listware
- Address: St. Leonards-On-Sea, TN37 7TA, UK
- Phone Number: +44 (0)142 439 01 40
2. NCC Group
NCC Group focuses on security assurance that is practical, repeatable, and tied to real attack behavior. The practice spans application and network assessments with options ranging from scoped checks to deeper simulation work such as red and purple teaming. Testers combine manual techniques with tooling to surface issues that matter for design, data flow, and build configuration, then translate findings into fixes that teams can actually ship.
For infrastructure, engagements cover external and internal paths, device and configuration reviews, and controls validation against policy or expected baselines. Where compliance matters, the group maps testing to frameworks and sector standards and supports regulated workloads without turning the exercise into paperwork. Recognition under the NCSC CHECK scheme and a clearly defined Technical Assurance Services portfolio underline a long, methodical focus on this craft.
Why this stands out:
- CHECK-listed status for network security testing under an established government scheme
- Coverage across app, network, and simulated attack exercises without overpromising scope
- Findings written for engineering handoff with clear remediation paths
Services include:
- Web, mobile, and native application security testing
- External and internal network penetration testing with configuration and build reviews
- Red, purple, and threat-led exercises to validate detection and response
- Code, architecture, and SDLC reviews tied to assurance goals
Contact Information:
- Website: www.nccgroupplc.com
- LinkedIn: www.linkedin.com/company/ncc-group
- Address: XYZ Building 2 Hardman Boulevard Spinningfields Manchester, M3 3AQ
- Phone: +44 (0) 161 209 5200
3. WithSecure
WithSecure treats offensive work as part of a broader assurance rhythm rather than a one-off stunt. Application testing is a core lane, delivered with established methods and an emphasis on realistic attack paths across web, mobile, and product surfaces. Consultants draw on active research and internal tooling from WithSecure Labs, which helps keep techniques current and reporting grounded in evidence. Cloud testing and hardening are available when the target lives in modern platforms, with attention to identity, secrets handling, and service configurations.
The team also shares opinions on where red teaming fits, advocating exercises that build capability rather than theatrics. That viewpoint shows up in how scoping is framed, how detection is measured, and how lessons flow back into day-to-day operations. Training options exist for hands-on skill building, which can be useful when the goal is to make fixes stick and keep drift in check. The overall feel is steady and outcome-focused, not flashy.
Standout qualities:
- Application security work delivered with mature, documented methodologies
- Active research culture and tooling that feed directly into testing techniques
- Clear stance on when red teaming helps and when other formats add more value
Services cover:
- Application and product penetration testing for web, mobile, and embedded targets
- Cloud security testing with focus on identity, configuration, and data paths
- Adversary simulation and detection-focused exercises where useful for the program
- Secure build and architecture reviews supported by research-driven guidance
Contact Information:
- Website: www.withsecure.com
- Twitter: x.com/withsecure
- LinkedIn: www.linkedin.com/company/withsecure
- Instagram: www.instagram.com/withsecure
- Address: Välimerenkatu 1 00180 Helsinki, Finland
- Phone: +358 9 2520 0700
4. Orange Cyberdefense
Orange Cyberdefense runs an ethical hacking practice that favors skilled manual testing backed by automation where it helps, not the other way around. Engagements range from quick spot checks to goal-oriented and threat-led campaigns that mirror how real attackers chain weaknesses to reach data. Reporting stays concrete, with exploit evidence, business impact, and prioritized fixes rather than noise. SensePost, the group’s long-standing hacking team, adds depth from public research and a history of offensive training.
On infrastructure, testing can start from the outside world or pivot from simulated phishing and exposed services to the internals, validating detection and response along the way. For applications and APIs, testers lean into logic flaws, auth boundaries, and unsafe integrations that scanners tend to miss. The practice is comfortable adjusting scope mid-stream when new paths appear, which keeps the work honest and useful for triage.
Training sits alongside delivery, using material built from real assessments to upskill engineers and security staff. That loop between hands-on testing, teaching, and published research helps the service avoid drift and preserves technique quality. The result is a service that feels investigative and grounded, not performative.
Why this provider stands out:
- Manual-first methodology that treats automation as support, not a finish line
- Portfolio that includes spot checks, goal-oriented work, and threat-led testing
- SensePost heritage with visible research output and practitioner-led training
Core offerings:
- External and internal infrastructure penetration testing with adversary simulation elements
- Web, mobile, and API assessments focused on logic, auth, and integration weaknesses
- Goal-oriented and threat-led campaigns to test real attacker objectives
- Spot-check engagements for targeted validation plus training based on assessment tooling
Contact Information:
- Website: www.orangecyberdefense.com
- E-mail: info@orangecyberdefense.com
- Twitter: x.com/orangecyberdef
- LinkedIn: www.linkedin.com/company/orange-cyberdefense
- Address: Avenue du Bourget 3, 1140 Brussels, Belgium
- Phone: +32 3 360 90 20
5. Outpost24
Outpost24 runs offensive security as an ongoing practice, not a once-a-year checkbox. The team blends deep manual testing with tuned automation so gaps show up fast and get triaged in a living portal rather than a static PDF. Web and API targets are pulled apart for logic issues, auth mistakes, and integration risks, while classic infrastructure tests probe exposed services and internal paths. When a goal needs to be proven end to end, red teaming and social engineering step in to show how issues chain together. Workflows can roll as PTaaS so testing stays closer to release cycles and change windows. It’s steady, methodical, and built for engineers who have to ship fixes.
Why people choose them:
- Hybrid approach that mixes manual depth with smart automation
- Real-time delivery via a portal that supports triage and handoff
- Options to escalate into red team and social paths when impact needs proof
- Cadence-friendly PTaaS so testing aligns with release timing
Core offerings:
- Application and API penetration testing with emphasis on logic and auth paths
- External and internal infrastructure testing with configuration and exposure review
- Goal-oriented red teaming and social engineering to validate detection and response
- PTaaS delivery with continuous assessment and ongoing retests
Contact Information:
- Website: outpost24.com
- E-mail: info@outpost24.com
- LinkedIn: www.linkedin.com/company/outpost24
- Instagram: www.instagram.com/outpost24_int
- Adress: Blekingegatan 1, 371 57 Karlskrona, Sweden
- Phone: +1 877 773 2677
6. SEC Consult
SEC Consult frames penetration testing as part of a broader assurance toolkit and keeps the craft anchored in repeatable methods. Application and infrastructure assessments are scoped with clear objectives, then executed with a balance of exploit technique and evidence capture that translates into practical fixes. The group maintains a Vulnerability Lab to study new tech and support high quality testing, which helps keep methodology current without drifting into hype. Cloud and container environments get their own treatment, with attention to identity, misconfiguration, and lateral movement risks.
Advisory work sits beside testing so lessons can fold back into build processes and control design. Reporting is structured, not theatrical, with concrete impact and remediation steps rather than noise. The public material around scope selection and benefits is straightforward, which makes planning easier for teams that have to fit testing into real delivery schedules. Overall, the service reads as measured and practical.
What they focus on:
- Structured methodology that favors evidence and reproducibility
- Laboratory research that feeds directly into test depth and coverage
- Dedicated coverage for cloud and container attack paths
- Advisory support to translate findings into durable controls
What they offer:
- Web, mobile, and product penetration testing with protocol and logic analysis
- External and internal network testing including privilege escalation paths
- Cloud and container testing across identity, configuration, and movement
- Secure development and architecture reviews tied to test outcomes
Contact Information:
- Website: sec-consult.com
- E-mail: office-germany@sec-consult.com
- Twitter: x.com/sec_consult
- LinkedIn: www.linkedin.com/company/sec-consult
- Address: Ullsteinstraße 130, Tower B/8. floor 12109 Berlin, Germany
- Phone: +49 (30) 398 20 2700
7. SySS
SySS operates as a specialist shop with a narrow lens on offensive work. Penetration tests are performed with real attacker behavior in mind, not just scanner output, and the sequence from scoping to exploitation to retest is clearly documented. The team publishes methodology material and white papers so stakeholders understand what is being tested and why it matters. That transparency makes handoff to engineering less painful.
When resilience needs to be validated against realistic threats, threat-led exercises are available. TLPT and TIBER-aligned engagements bring dedicated threat intelligence and a disciplined red team into the same storyline, which helps regulated environments measure what actually breaks under pressure. The approach stays controlled and evidence heavy, which is essential when regulators or auditors will look closely at the results.
Response time can be tight when needed. Agile testing options start quickly and run remotely with minimal prep, useful when a release window is close or an exposure needs immediate validation. Communication remains deliberate throughout so changes in scope or newly discovered paths can be handled without drama. Straightforward and calm.
Standout qualities:
- Clear, published methodology that demystifies the testing process
- Options for TLPT and TIBER-aligned exercises when threat realism is required
- Emphasis on business logic and real attacker chaining rather than scanner noise
- Agile start options for time sensitive assessments
Services include:
- Application and API testing with focus on logic flaws and auth boundaries
- Internal and external infrastructure testing with realistic attack patterns
- Threat-led exercises including TLPT and TIBER style assessments
- Agile remote testing with rapid kickoff and structured retests
Contact Information:
- Website: www.syss.de
- E-mail: info@syss.de
- LinkedIn: www.linkedin.com/company/syss-gmbh
- Instagram: www.instagram.com/syssgmbh
- Address: Schaffhausenstraße 77 72072 Tübingen, Germany
- Phone: +49 7071 407856-0
8. Usd AG
Usd AG runs security testing as a craft with a clear playbook and steady research to back it up. Engagements span web, mobile, APIs, and classic infrastructure, with specialists focusing on logic errors, authentication gaps, and unsafe integrations alongside service exposure and misconfiguration checks. The practice publishes findings through Usd HeroLab, which keeps techniques sharp and helps stakeholders see real evidence, not guesswork. Where depth is needed, options range from structured approaches aligned to recognized standards to niche areas like mainframe analysis. Reporting is practical, remediation friendly, and follows through to retest so fixes actually land. Calm, methodical, repeatable.
Why this stands out:
- Ongoing research output via Usd HeroLab that feeds day to day testing
- Structured approach mapped to recognized methods for consistent quality
- Coverage that reaches beyond web apps into APIs, infrastructure, and even mainframes
- Reporting aimed at engineering handoff with evidence and clear follow through
Core offerings:
- Web and mobile application security testing with emphasis on business logic and auth paths
- API assessments that simulate realistic abuse of authentication, input handling, and configuration
- External and internal infrastructure testing with exposure analysis and configuration review
- Retest and assurance cycles anchored in a documented penetration testing approach
Contact Information:
- Website: www.usd.de
- E-mail: contact@usd.de
- LinkedIn: www.linkedin.com/showcase/usd-ag-international
- Address: Frankfurter Str. 233 Forum C1, 2. Floor 63263 Neu-Isenburg, Germany
- Phone: +49 6102 8631-0
9. Pen Test Partners
Pen Test Partners treats offensive work as an engineering routine, not theater. Application testing covers web and API surfaces with careful attention to auth boundaries, data flow, and integration risk. Infrastructure assessments look at internal and external paths, privilege movement, and the controls that should catch missteps. The team explains scope and depth in plain language, then delivers findings with enough detail to fix, not just file.
For fast moving products, the group offers PTaaS so tests can align with release windows without losing the manual depth that finds real issues. When broader realism is required, campaigns simulate how weaknesses chain together to reach goals. The tone is measured and evidence first. No drama, just work.
Standout qualities:
- Manual depth applied to apps, APIs, and networks rather than scanner noise
- Clear scoping and reporting that keep the focus on fixable impact
- Options for PTaaS to fit frequent change and CI style delivery
- Ability to pivot from point checks to goal oriented attack simulation when needed
What they offer:
- Web and API penetration testing with tailored test design and exploit evidence
- Internal and external network testing with lateral movement and control validation
- PTaaS to call off testing effort around changes while retaining manual assurance
- Code aware reviews and application centric assessments that feed straight into remediation
Contact Information:
- Website: www.pentestpartners.com
- Twitter: x.com/PentestPartners
- LinkedIn: www.linkedin.com/company/pen-test-partners
- Address: Unit 2, Verney Junction Business Park, Buckingham, MK18 2LB, UK
- Phone: +44 20 3095 0500
10. IT Governance
IT Governance provides a structured penetration testing service with a strong emphasis on tailoring scope to the environment. Work spans networks, applications, and wireless surfaces, with test levels adjusted after scoping so depth matches risk and complexity. The practice highlights CREST accreditation and keeps language around delivery specific and practical. The result is predictable testing and reports that translate cleanly into action lists.
The catalog is broad without being vague. External and internal network checks, web application reviews, wireless testing, and social engineering are all available with clear definitions and boundaries. PCI oriented testing can be planned when cardholder data systems are in scope. That helps compliance teams line up evidence without reinventing the wheel.
Process wise, communication starts with scoping and ends with remediation advice. Packages exist for simpler needs, while more complex environments get additional technical support and custom test design. The tone stays consultative and grounded, which makes it easier to fit assessments into normal delivery cycles.
Why people like them:
- CREST accredited service with clearly described test types and levels
- Scoping that calibrates depth before testing starts for predictable outcomes
- Coverage across external and internal networks, web apps, wireless, and social paths
- Support for PCI focused testing when payment systems are in play
Their services include:
- External and internal network testing with exploit driven validation
- Web application assessments with hands on analysis beyond automated tooling
- Wireless and remote access reviews plus social engineering exercises
- PCI aligned testing and tailored scoping with remediation guidance
Contact Information:
- Website: www.itgovernance.co.uk
- E-mail: clientservices-uk@grcsolutions.io
- Facebook: www.facebook.com/ITGovernanceLtd
- Twitter: x.com/ITGovernance
- LinkedIn: www.linkedin.com/company/it-governance
- Address: Unit 3, Clive Court Bartholomew’s Walk Cambridgeshire Business Park Ely, CB7 4EA United Kingdom
- Phone: +44 (0)333 800 7000
11. Dionach
Dionach treats offensive testing as a disciplined practice with room for curiosity when the target resists. Work spans internal and external infrastructure checks, application assessments for web and mobile, and deeper campaigns that follow realistic threat intelligence. The practice runs specialised exercises for AI-enabled systems, looking for prompt abuse, data leakage, and other failure modes that typical app tests miss. Where a higher bar is required, engagements align to threat-led schemes so detection and response can be judged against credible tactics. Industrial environments are not ignored either, with OT and ICS reviews that respect the peculiarities of those stacks. Credentials in well known schemes round out a methodical approach that prefers evidence over theatrics.
Standout qualities:
- Recognition under established assurance schemes for penetration testing
- Threat-led exercises aligned to frameworks such as TIBER-EU and similar programs
- Specialist testing for applications using machine learning and large language models
- Capability to assess OT and ICS environments alongside traditional IT
Core offerings:
- Internal and external network penetration tests with configuration and exposure analysis
- Web and mobile application assessments focused on logic flaws and authentication boundaries
- AI application security exercises probing prompt abuse, data handling, and model behavior
- Threat-informed campaigns and retests to validate fixes and strengthen response
Contact Information:
- Website: www.dionach.com
- E-mail: hello@dionach.com
- Facebook: www.facebook.com/DionachCyber
- Twitter: x.com/DionachCyber
- LinkedIn: www.linkedin.com/company/dionach-ltd
- Instagram: www.instagram.com/dionachcyber
- Address: Unipart House Garsington Road Oxford OX4 2PG
- Phone: +44 (0)1865 877830
12. Bulletproof
Bulletproof positions testing as a repeatable service that ships findings through a live portal rather than static paperwork. Application work covers web, APIs, and mobile, while infrastructure engagements check services, patching, and common misconfigurations. Delivery includes automated scans alongside human-led testing so new risks appear in the dashboard without waiting for the next engagement. Accreditation and individual tester certifications are published up front, which keeps expectations clear from scope to handoff.
When campaigns need to model attacker behavior, options extend to social engineering and red team style work. Cloud surfaces are explicitly in scope, with configuration reviews and platform-specific checks. Reporting focuses on impact, likelihood, and fix paths so engineering teams can move without guesswork. The rhythm fits ongoing programs or one-off spot checks as needed.
Key points:
- Portal-based reporting with prioritisation and remediation guidance
- Automated scans bundled with testing to surface emerging issues between cycles
- Coverage across apps, networks, mobile, cloud, social paths, and goal-oriented exercises
What is provided:
- Web and API security testing with authenticated and unauthenticated paths
- Infrastructure reviews including external and internal assessments against best practice
- Cloud assessments with configuration validation across major platforms
- Social engineering and red team exercises to test detection and response
Contact Information:
- Website: www.bulletproof.co.uk
- E-mail: contact@bulletproof.co.uk
- LinkedIn: www.linkedin.com/company/bulletproof-cyber-limited
- Address: Unit H Gateway 1000 Whittle Way Stevenage Herts SG1 2FP
- Phone: 01438 500 093
13. Pentest People
Pentest People builds delivery around PTaaS so testing and triage live in a platform, not just a report. SecurePortal is the hub for results, evidence, and continuous vulnerability monitoring, giving stakeholders a single place to track remediation over time. Traditional consultant-led engagements are still the backbone, but the platform smooths scoping, retest, and communication. The combination keeps cadence tight without flattening the work into pure automation.
Service lines include application testing for web and APIs, infrastructure checks, and cloud coverage, with definitions that avoid ambiguity at scope time. Accreditation in industry schemes is documented publicly, and the portfolio describes options from one-time assessments to recurring memberships. Packages step up features rather than inflating claims, which makes it easier to fit tests into real release calendars. The emphasis is practical and evidence-first.
When a goal needs to be proven end to end, testers pivot to campaigns that chain weaknesses to demonstrate impact. The team also publishes explainers and service walkthroughs so stakeholders know what to expect before the first payload is sent. That transparency shortens the distance between finding and fix, which is usually the point. Routine, but not rote.
Why people choose this service:
- Platform-supported delivery that keeps results and retests in one place
- Consultant-led testing combined with continuous monitoring under PTaaS
- Clear scoping across application, infrastructure, and cloud surfaces
- Public accreditation and service definitions that set expectations early
Service scope:
- Web and API testing with attention to logic, session handling, and integration risk
- Infrastructure assessments covering external exposure, internal movement, and control gaps
- Cloud configuration and access reviews linked to platform specifics
- PTaaS delivery via SecurePortal with ongoing visibility and structured retests
Contact Information:
- Website: www.pentestpeople.com
- E-mail: info@pentestpeople.com
- Facebook: www.facebook.com/pentestpeople
- Twitter: x.com/pentestpeople
- LinkedIn: www.linkedin.com/company/pentestpeople
- Address: 20 Grosvenor Place, London, United Kingdom, SW1X 7HN
- Phone: 0330 311 0990
14. Squalio
Squalio runs security engagements with a practical bend, leaning on penetration tests that target real systems rather than abstract checklists. Scopes cover web applications, APIs, mobile apps, classic network layers, and cloud setups, with reports mapped to specific weaknesses and the paths to fix them. For asset-heavy environments, testing extends into OT and ICS, where small misconfigurations can snowball into downtime or data exposure. Work often pairs manual probing with tooling to sort signal from noise, then folds findings into a clean remediation plan. Around the core service sit related capabilities like cybersecurity advisory, managed SOC, and phishing simulations, which help sustain improvements between test cycles.
Standout qualities:
- Coverage across web, API, mobile, cloud, network, and industrial systems
- Balance of hands-on testing with automation to validate real risk
- Adjacency to advisory and SOC services for follow-through after tests
- Public guidance and events that translate testing insights into practice
Core offerings:
- Web and API security testing with manual verification of high-impact flows
- Infrastructure and cloud attack-surface assessments with exploit validation
- OT and ICS penetration exercises focused on safety and continuity risks
- Mobile application security testing across data at rest and runtime
- Vulnerability assessment plus governance support via vCISO when required
Contact Information:
- Website: squalio.com
- E-mail: squalio@squalio.com
- Facebook: www.facebook.com/SqualioGlobal
- LinkedIn: www.linkedin.com/company/squalio-global
- Address: Kr. Valdemara 21-19, Riga, LV1010, Latvia
- Phone: +371 6750 9900
15. DataArt
DataArt treats offensive testing as an engineering discipline, not a stunt. The team offers pentesting as a service with clear cadences, scoping, and evidence that traces each finding to a real attack path. Approaches span black box, grey box, and targeted assessments for networks and applications, with reporting designed to land inside existing delivery routines. For modern stacks, coverage includes mobile, web, and cloud surfaces, plus secure code review for issues that hide below the UI layer.
Where testing needs to mirror current threats, the catalog reaches into red teaming and specialized work for AI and LLM-driven applications. The intent is straightforward. Start with scoped checks to surface the obvious, then escalate to goal-driven simulations when leadership needs proof of resilience. Throughout, the emphasis stays on reproducible results and actionable fixes rather than theatrics.
Why people choose this provider:
- Structured PTaaS model with repeatable workflow and clear evidence trails
- Range from classic web and network tests to mobile and cloud scenarios
- Options for red teaming and AI-focused testing when realism is the priority
- Secure code review to catch design flaws that scanning misses
Their focus areas:
- Penetration testing as a service with black-, grey-, and targeted methods
- Network, web, and mobile penetration tests aligned to business impact
- LLM and AI application penetration testing for prompt and model risks
- Red teaming and adversary emulation for measurable resilience goals
- Secure code review to reduce latent vulnerabilities in core modules
Contact Information:
- Website: www.dataart.com
- E-mail: hr-uk@dataart.com
- Facebook: www.facebook.com/DataArt
- Twitter: x.com/DataArt
- LinkedIn: www.linkedin.com/company/dataart
- Address: 55 King William Street, 3rd floor, London, EC4R 9AD
- Phone: +44 (0) 20 7099 9464
Conclusion
Penetration testing is about real attack paths, not a checkbox. Across Europe it sits next to DevSecOps and cloud delivery as routine engineering. The aim is simple: surface issues before release and close them without drama. Choosing a vendor shapes half the outcome. Look for method, manual depth, transparency, and retesting. Accreditations like CREST or CHECK help, but they do not replace practitioner skill. Read the report quality: evidence, clear remediation steps, priorities. You also need live channels – a portal, fix tracking, agreed timelines.
Coverage should span web, APIs, networks, cloud, and when needed mobile and OT. Make sure testing fits your cadence – sprints, change windows, audits. One more thing. Start with sensible scope, then grow into scenarios and threat modeling. That keeps pentesting a useful tool, not a show.
