Find a pentest company with ISO 27001
1532 companies have this certification
DigitalXRAID
Cybersecurity company specializing in penetration testing and security services; provides CREST-accredited web and internal penetration testing with active attack simulation capabilities; based in the United Kingdom with 39 employees and $8.6M annual revenue.
Punk Security Limited
UK-based IT services and consulting company specializing in DevSecOps, cybersecurity, and cloud engineering; 6 employees, founded 2021, with a focus on penetration testing, governance support, and cloud security services.
Closed Door Security
UK-based private cybersecurity company specializing in penetration testing, security assessments, engineering, and certification; CREST-accredited, partner of SBRC & Police Scotland, with 4 employees and 33.3% YoY growth; actively promotes penetration testing services through dedicated pages and certifications.
Cognisys
UK-based IT services and cybersecurity company specializing in penetration testing, security assessments, and compliance; 63 employees with 95.5% YoY growth; founded in 2017; CREST-accredited penetration testing services; headquartered in Leeds, UK.
Paul Reynolds Cyber Security
Cybersecurity firm based in Solihull, UK, with additional operations in Dubai, UAE; provides penetration testing (pentest) services including PTaaS and certified testing teams, emphasizing offensive security expertise.
Jumpsec
UK cybersecurity firm Jumpsec Limited offers bespoke consultancy and CREST-certified penetration testing services, including application and threat-led pentests; based in London and Surrey, emphasizing technical excellence and expert-driven approaches.
Brigantia by Elovade
UK-based IT services and cybersecurity consulting company with 30 employees, founded in 1996; specializes in cybersecurity solutions, including penetration testing via Rootshell, and supports channel partners with recurring revenue growth; part of the Elovade Group, with a focus on security assessments, red team engagements, and managed services.
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Prism Infosec
Cybersecurity firm based in Cheltenham, UK, specializing in penetration testing, red teaming, and GRC services; provides assessments, testing, and response solutions to enhance security posture.
CyPro
CyPro is a UK-based private cybersecurity firm specializing in computer and network security, with 15 employees and 16.7% YoY growth since 2022. It explicitly offers penetration testing services that simulate attacks to uncover vulnerabilities, supporting high-growth companies in scaling their security capabilities and gaining client trust.
Blackfoot Cybersecurity
Cybersecurity company specializing in computer and network security, penetration testing, and compliance; 15 employees with +20.8% YoY growth; founded in 2008; headquartered in Welwyn Garden City, UK; offers services including installation, gas washing, ventilation, and equipment manufacturing; active in cyber security training and risk management.
CyberQ Group
CyberQ Group is a UK-based private cybersecurity firm specializing in cyber protection and penetration testing services; 27 employees, founded in 2017, with $6.3M in funding, providing 24/7 global support and known for a reactive, technology-driven approach to cybersecurity.
Dionach
Cybersecurity firm based in Oxford, UK, specializing in penetration testing and security assessments; CREST-accredited with a comprehensive suite of security services. Part of Nomios; founded in the UK.
Cyber Vigilance
Cyber Vigilance is a UK-based cybersecurity firm headquartered in Guildford, UK; specializes in penetration testing services that identify vulnerabilities in infrastructure and applications, including automated pentesting capabilities through Horizon3.ai partnership.
Kocho
UK-based cybersecurity firm specializing in Microsoft identity, security, and cloud solutions; offers penetration testing services and security consulting; registered in England and Wales (company number 04308824), with a London office.
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CyberFortis Consulting
UK-based IT and cybersecurity consulting firm specializing in penetration testing, threat intelligence, risk assessments, and compliance services; 4 employees; founded 2019; offers explicit pentest services; serves clients across UK, EU, Australia, New Zealand, and USA.
Exponential-e
UK-based IT services and consulting company providing secure cloud, connectivity, cyber, and voice solutions; 492 employees, $255.7M revenue, founded 2002, headquartered in London. Offers penetration testing, red team testing, and website security testing, with a focus on active cybersecurity testing and exploitation simulation.
Reliance Cyber
Reliance Cyber is a UK-based IT services and cybersecurity consulting company with 48 employees and $5M-$25M annual revenue; specializes in penetration testing, threat intelligence, incident response, and managed security services, with a focus on safeguarding organizations in the digital landscape.
Closed Door Security
UK-based cybersecurity firm specializing in penetration testing and security assessments; registered in the UK (SC585645), headquartered in Stornoway, UK; offers professional pentest services as highlighted on their website and supported by external sources.
Pentest Limited
UK-based cybersecurity company founded in 2019; registered at 22 Great James Street, London, with company number 11925182; provides manual penetration testing, red teaming, and security consultancy services.
4N6
IT services and consulting company specializing in cybersecurity, troubleshooting, diagnostics, post-incident reviews, and digital forensics; offers full penetration testing services including active exploitation, vulnerability analysis, and remediation; based in London, UK with 1 employee, 1,122 monthly website visits, and ranked #11,322,919 globally.
BSI Cyber Consulting
Cybersecurity company specializing in penetration testing, red team assessments, and information security services; supports CREST-certified pentest offerings and detailed testing procedures; 2 employees, $9.44M revenue, headquartered in Cambridge, UK.
Boxxe
UK-based IT solutions provider specializing in hardware, software, managed IT services, and cybersecurity; explicitly offers penetration testing (pentest) services as part of its cybersecurity portfolio; registered in England and Wales with a York headquarters.
Securious - Data and Cyber Security
Cybersecurity compliance and pentesting company based in Exeter, UK; 11 employees with 18.2% YoY growth; founded in 2007; provides PCI DSS, ISO 27001, Cyber Essentials, and penetration testing services to UK and international clients.
Xpertex Ltd
UK-based IT services and consulting firm specializing in cybersecurity, including penetration testing and breach & attack simulation; 9 employees with -6.7% YoY growth; founded 2006; headquartered in Welwyn Garden City, England; active in security assessments, vulnerability analysis, and machine parts manufacturing.
Zepko
Cybersecurity firm based in Guildford, United Kingdom, specializing in penetration testing; offers detailed security assessments using standardized testing methodologies and emphasizes human intervention to enhance resilience.
Cybergen® Security
Cybergen® Security is a UK-based IT services and cybersecurity consulting firm founded in 2023, with a focus on penetration testing, red teaming, and threat mitigation. The company provides CREST-accredited penetration testing and 24/7 managed detection and response, emphasizing proactive security testing and vulnerability identification, despite having only 1 employee.
Protection Group International
Protection Group International is a UK-based security and investigations firm specializing in digital resilience, security consulting, and cyber security services; with 77 employees (+10.6% YoY growth), $15M annual revenue, founded in 2013 in London. PGI provides CREST-aligned penetration testing services, demonstrating formal technical standards, and serves a global client base including governments and NGOs. The company operates in multiple languages and maintains active social media engagement.
GoDefend (Cyber Security)
Cybersecurity company based in the United Kingdom; specializes in data security software, penetration testing, breach detection, and compliance solutions; 5 employees, founded 2018, $3.3M funding, recent £250K investment to grow threat detection tech; competes with qingteng cloud security and sonet.io.
ResilientX Security
Cybersecurity company specializing in penetration testing, attack surface management, and third-party risk solutions; provides active testing and simulated attack services with a focus on web, cloud, and network security; 10 employees; Founded 2022; London, UK.
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Bridewell
Cybersecurity company based in Reading, UK, specializing in computer and network security; 224 employees (+7.9% YoY growth), $6.0M revenue, founded 2013; provides penetration testing and security consulting, trusted by critical infrastructure organizations and highly regulated sectors.
CYFOR Secure | Cyber Security
Cybersecurity company based in Manchester, UK, with $4.1M annual revenue; specializes in penetration testing, digital forensics, incident response, vulnerability assessments, dark web monitoring, and cybersecurity audits; founded in 2002.
CyberCX
UK-based cybersecurity company providing penetration testing, incident response, vulnerability assessments, and governance, risk, and compliance services; explicitly signals UK origin and offers detailed pentest solutions.
tmc3
IT services and cybersecurity company based in the United Kingdom; 20 employees with 27.3% YoY growth; founded in 2021; specializes in penetration testing, data protection, security assurance, and secure development lifecycle for government, critical infrastructure, and healthcare sectors.
Cyberfort
UK-based cybersecurity firm specializing in penetration testing services such as code reviews, cloud security testing, AI/LLM testing, and application/web/network/internals testing; performs active attack simulations to identify vulnerabilities.
Acutest
UK-based software testing and quality assurance consultancy; offers penetration testing services; registered in York, England, with additional UK addresses; specializes in testing software, business processes, and IT to improve digital transformation projects.
BT Group
UK-based telecommunications company with 30,295 employees and GBP20.4B annual revenue; operates the largest fixed and mobile networks in the UK; provides active cybersecurity services including penetration testing and ethical hacking; GBP137.8M market cap; over $8.7B in funding; headquartered in London, UK.
BreachLock
Cybersecurity firm based in London, UK, providing penetration testing, attack surface discovery, and red teaming services; offers continuous security testing and evidence-backed attack surface management.
Prolifics Testing
UK-based cybersecurity company specializing in penetration testing; employs CREST-certified professionals; offers internal and external testing for networks, web, mobile, and APIs; registered in the UK with company number 03814910; principal office in Borehamwood, Hertfordshire.
KiwiQA
UK-based software testing company specializing in penetration testing; explicitly offers pentest services to reduce security risks, with a UK address at Vista Business Centre, Hounslow, TW4 6JQ. Provides comprehensive QA and testing solutions.
PwC
UK-based professional services firm with 120,836 employees and $55.4B revenue; offers assurance, tax, advisory, and cybersecurity services including penetration testing and ethical hacking (CREST-accredited); registered office at 1 Embankment Place, London; operates globally with a network of over 370,000 staff in 149 countries.
Predatech
UK-based IT services and cybersecurity consultancy specializing in penetration testing, vulnerability management, and security certifications; 8 employees with 28.6% YoY growth since 2020; offers CREST-accredited pentest services and helps organizations enhance cyber defenses.
Netcentrix
UK-based IT managed services provider specializing in cloud, infrastructure, security, and professional services; offers penetration testing services as indicated in their terms and conditions; registered in England with company number 03076196, headquartered in Buckshaw Village, Chorley, Lancashire.
3B Data Security
UK cybersecurity company specializing in incident response, compliance, forensic investigations, and penetration testing; headquartered in Tunbridge Wells with operational address in Sawston, Cambridge; offers penetration testing services and extensive security consulting.
Tranchulas
Cybersecurity company specializing in penetration testing, red teaming, and threat intelligence; 11 employees with 20% YoY growth; founded in 2006; headquartered in London, UK; offers offensive and defensive cyber solutions, ISO 27001, incident response, and cyber training.
Periculo
UK-based IT services and cybersecurity consultancy with 11 employees, founded in 2015; specializes in cybersecurity for digital health including Penetration Testing, Cyber Essentials, ISO 27001, and Medical Device Security; 18.2% monthly growth, 1,720 monthly visits, ranked #8,134,692 globally.
Evolve North Ltd
UK-based consultancy specializing in Governance, Risk, and Compliance, and IT Security and Assurance; provides penetration testing services to identify and remediate vulnerabilities in IT environments; headquartered in Durham, England, with registered office in North Yorkshire.
CyberOne
CyberOne (Comtact Ltd.) is a UK-based private cybersecurity firm specializing in proactive security testing, including CREST-accredited penetration testing; 51 employees with +23.4% YoY growth; $12M annual revenue; founded in 2005; offers integrated security solutions such as identity management, email, internet, and network security; recognized as one of 100 global Microsoft partners.
SMARTSEC Information Security
UK-based cybersecurity consultancy founded in 2019 with 3 employees; specializes in penetration testing, Web3 & AI security, security operations, and vCISO advisory; offers comprehensive security solutions and compliance services.
SureCloud
UK-based GRC and risk management software provider; offers penetration testing services including PTaaS with CREST accreditation; headquartered at 1 Sherwood Street, London W1F 7BL, England.
EJN Labs
UK-based private cybersecurity firm specializing in AI-powered cyber defense, including penetration testing, red teaming, and bug bounty; CREST certified; 3 employees; Founded 2022; Headquarters in United Kingdom.
TIEVA
UK-based IT services and consulting company specializing in transformative business IT solutions, multi-cloud strategies, and cybersecurity, including penetration testing services; 135 employees (+0.6% YoY growth); founded 2007; headquartered in Leeds, UK.
FluidOne
UK-based IT services and consulting firm specializing in secure data, voice, and cloud solutions; offers penetration testing and cybersecurity services; 152 employees, $132.4M revenue, founded 2006, headquartered in London, UK; recognized for high NPS and recent UK expansion.
URM
URM (URM Consulting Services Ltd) is a UK-based business consulting firm specializing in information security and risk management; 42 employees with 36.4% YoY growth, $1M-$5M revenue, founded in 2005, headquartered in Reading, UK. The company provides penetration testing, vulnerability assessment, ISO 27001, GDPR, PCI DSS, and business continuity services, with a global rank of #1,589,893 and 14,482 monthly visits.
Laburity
Cybersecurity services provider based in the United Kingdom; specializes in vulnerability assessments, penetration testing, compliance, and code analysis; 9 employees; Founded 2022; Offers active penetration testing services and holistic cybersecurity solutions.
SRM - Security Risk Management Ltd
UK-based private information services company founded in 2002; specializes in cybersecurity with explicit penetration testing services to identify vulnerabilities; 4 employees, $6.5M revenue, $16.7K seed funding, part of Arcanum Group, with recent activity in security collaborations and innovations.
CyberWhite Ltd
CyberWhite Ltd is a UK-based cybersecurity consultancy specializing in penetration testing, risk mitigation, and security assurance; with 8 employees, founded in 2018, and a client-focused approach that emphasizes tailored security solutions, training, and compliance in cybersecurity standards.
Barefoot Cyber
Cybersecurity company headquartered in the United Kingdom; specializes in penetration testing services with proven ability to scope, review, and execute pentest engagements.
RightCue
Cybersecurity consulting firm specializing in compliance and penetration testing; 14 employees (+26.7% YoY growth); CREST-certified pentest services; Founded 2009; Basingstoke, UK.
Nellcote Ltd
UK-based private cybersecurity firm specializing in penetration testing and security consultancy; 5 employees with 33.3% YoY growth, founded in 2017, CREST accredited with expertise in active attack simulations across multiple environments, emphasizing personalized IT and cybersecurity services.
Cybergen Security
UK-based cybersecurity company specializing in CREST-accredited penetration testing services; headquartered in Witney, Oxfordshire, with a focus on security testing and incident response.
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cydentity.co.uk
UK-based cybersecurity firm specializing in proactive, business-driven protection; offers penetration testing and attack simulation services, including ransomware attack simulations; 2 employees; Founded 2025; Wales, UK.
Samurai Digital Security Limited
Cybersecurity provider specializing in penetration testing, network intrusion, incident response, and information governance; UK-based with 4 employees, $1M-$5M revenue, founded 2016; NCSC certified, serving government and institutions, with CREST accreditation for penetration testing services.
Koris365
UK-based IT and security managed service provider; offers penetration testing with customized automated and manual assessments, and cyber security evaluations; registered in England (Company No. 07709017), headquartered in Hemel Hempstead.
DefensityOne
DefensityOne is a cybersecurity solutions provider based in Milton Keynes, UK, specializing in proactive threat detection, risk management, and digital defense services. The company has 7 employees, was founded in 2015, and focuses on penetration testing, data security, and managed services, with an 18.8% YoY employee decline.
Digital Insights Consultancy
Cybersecurity company based in Milton Keynes, UK; specializes in penetration testing, incident response, digital forensics, and SOC services; 3 employees with -44.4% YoY growth; founded 2019; offers tailored cybersecurity solutions including infrastructure and cloud pentest services.
Acumen Cyber
Acumen Cyber is a UK-based private cybersecurity firm with 23 employees and +40.9% YoY growth, providing 24/7 security services including MXDR, SaaS, cloud, email, web, DNS security, vCISO, and penetration testing; recognized for security testing capabilities and CREST accreditation.
Omnicyber Security
Cybersecurity firm based in the UK and Canada; specializes in penetration testing, managed security, and compliance services; explicitly states penetration testing as a core service and UK presence.
GRC International Group
Cybersecurity company specializing in computer and network security; provides penetration testing services as part of its cyber-defense solutions; 25 employees; GBP 14.7M annual revenue; GBP 8.4M market cap; based in Ely, UK; operates in cybersecurity, IT services, consulting; global rank #8,652,681; 1,467 monthly website visits.
Vorago Security
UK-based cybersecurity company specializing in penetration testing; headquartered in Doncaster, England, with a registered office at 1 Water Vole Way, DN4 5JP; active provider of security testing services, including penetration testing, as detailed on their website.
Purecyber Limited
UK cybersecurity firm based in Cardiff; provides penetration testing, red teaming, and threat detection services; CREST-certified penetration testing capability; trusted by organizations worldwide.
Akita
UK-based IT company specializing in managed IT services and cybersecurity; offers CREST-accredited penetration testing services with headquarters in Sevenoaks, Kent, and Wrotham, Kent.
EY
Global professional services firm based in London, UK, with 279,628 employees and $51.2B revenue; offers advisory, assurance, tax, financial, and cybersecurity services including penetration testing and red teaming; competes with Deloitte and Accenture; active in public sector initiatives and social media.
Rmg Cyber
Cybersecurity firm based in Lincolnshire, UK; offers penetration testing, auditing, cybersecurity training, risk management, cloud security, and software development services; specializes in web application pentesting with a focus on identifying vulnerabilities and providing remediation.
Cyber Security Specialists
Cyber Security Specialists is a UK-based private cybersecurity consultancy specializing in security consultancy, managed security services, and CREST-accredited penetration testing; 15 employees with 29.6% YoY growth; offers enterprise security architecture, information security, cloud security, security testing, and third-party assurance services.
SSL247 (A Sectigo Company)
UK-based private IT security firm founded in 2003; provides web security, SSL, PKI, and penetration testing services; 19 employees, $5M revenue; operates in 18 markets globally; offers certified pentest services, security audits, incident response, and digital identity solutions; ranked #2,692,341 globally and #271,928 in the UK.
Sytech
UK cybersecurity consulting firm specializing in penetration testing; provides controlled, accredited cyber attack simulations for public and private sector clients across the UK, including police forces and government agencies.
KPMG
Global professional services firm specializing in accounting, advisory, and consulting; 47,522 employees, $36B revenue, headquartered in London, UK; offers penetration testing services with CREST accreditation, serving multiple industries and markets.
Css Assure
UK-based cybersecurity firm specializing in security & compliance, including penetration testing, data protection, and certification programs; registered at No.1 Colmore Square, Birmingham, UK, as Cyber Security Strategies Ltd (Company No. 11070817). Offers technical services such as vulnerability scanning and penetration testing, with dedicated pages and blog content highlighting their expertise.
Cyber Fortify
UK-based cybersecurity firm providing penetration testing services; offers web, API, mobile, and network pentests with a focus on real-world vulnerabilities; registered at 24 Mill Holme Drive, Brotton, England, TS12 2UR; active company supporting ongoing UK registration.
Spritzmonkey
Cybersecurity consultancy based in the United Kingdom; specializes in CREST-certified penetration testing and vulnerability scanning services, actively marketing these capabilities and participating in industry events as a recognized provider.
INTEX IT
IT services and consulting company specializing in information security; provides penetration testing, security audits, data protection, PCI compliance, and security awareness training; based in Chatham, UK, founded 2002, with 2 employees; focuses on security consultancy and compliance services.
Cybernitics
Cybernitics is a UK-based cybersecurity firm specializing in offensive security, including red teaming and penetration testing; it offers attack simulations and threat emulation services to help organizations identify vulnerabilities.
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Intersect
Cybersecurity company headquartered in Manchester, UK; specializes in penetration testing and security assessments, offering simulated real-world attack services to identify vulnerabilities.
Intrinsic Security
Cybersecurity company specializing in penetration testing, threat detection, and incident response; 19 employees with 71.4% YoY growth; founded 2023; based in Peterborough, UK; offers vulnerability management, cyber threat intelligence, and attack surface management.
Xalient
IT services and consulting company specializing in modern networking, security, and communications; 205 employees (+22.8% YoY growth), $45.3M revenue; offers penetration testing services; founded 2015; headquartered in Leeds, UK.
Sovereign Secure Ltd
UK-based IT services and consulting company specializing in PCI DSS compliance, security assessments, and penetration testing; 10 employees with 25% YoY growth, founded in 2012, with global offices in the UK, US, Singapore, and Middle East; provides API, web, network, cloud, and cybersecurity testing services.
AVUL
Cybersecurity company specializing in penetration testing, risk assessment, and consulting; based in São Paulo, Brazil, with 2 employees since 2019, focusing on digital resilience and cybersecurity services aligned with NIST standards.
BNF Cyber Security
Cybersecurity company specializing in penetration testing, detection and response, cloud security, and vulnerability management; founded in 2020, based in Rio de Janeiro, Brazil, with 4 employees and 700% YoY growth.
Shield Security
Cybersecurity company headquartered in São Paulo, Brazil, providing penetration testing (pentest) services; features attack simulation offerings to test security defenses.
Contego Security
Brazil-based cybersecurity consulting firm specializing in security compliance and penetration testing; offers services including penetration testing (pentest) to identify security vulnerabilities, supported by educational content on the importance of pentests for cybersecurity.
BITS PROTECTOR
IT services and consulting firm specializing in information security; offers penetration testing, security program implementation, ISO 27001, risk management, and training; based in São Paulo, Brazil, founded in 2020, with 7 employees and 10% annual growth.
Conviso Application Security
Cybersecurity company specializing in application security; 55 employees with 3.9% YoY growth; based in Curitiba, Brazil; offers penetration testing, offensive security, and red-team services, with over 16 years of experience serving financial institutions and global clients.
Raidbr
Raidbr is a Brazil-based IT services and consulting firm specializing in outsourcing, cloud solutions, LGPD compliance, and security testing, including penetration testing services; with 20 employees, $413.1K annual revenue, founded in 2002, and recognized as a regional leader in security and technology.
Enygma Tech
Brazilian cybersecurity firm specializing in IT security, network protection, and penetration testing; offers AI-driven automated pentests; 14 employees with 22.7% YoY growth; founded in 1995; based in São Bernardo do Campo, São Paulo, Brazil.
Data Guide
Brazil-based private IT & Services company founded in 2020; 19 employees with 22.2% YoY growth; specializes in data protection, privacy compliance (LGPD, GDPR), and offers DPO-as-a-Service, Security-as-a-Service, and penetration testing services for web, mobile, API, and network systems; 1,699 monthly website visits; ranked #5,715,591 globally.
Brute Force Security
Brazilian private cybersecurity firm founded in 2019; specializes in security, infrastructure, and preservation of acervos with services including penetration testing, LGPD compliance, WAF, VPN, and honeypots; 1-10 employees, -100% YoY growth, 1,056 monthly visits, ranked #11,234,321 globally and #594,094 in Brazil.
Tenchi Security
Tenchi Security is a Brazil-based cybersecurity firm founded in 2019, specializing in third-party risk management, privacy, and penetration testing services; 55 employees with 17.3% YoY growth, $3.5M annual revenue, and $10.3M in total funding, last raised in Series A in 2024. It is recognized in Gartner’s Market Vendor Guide and operates in categories including cybersecurity, TPRM, cloud security, and DevSecOps.
Stefanini Cyber
Brazil-based IT services and cybersecurity company specializing in managed security services, penetration testing, vulnerability analysis, and threat detection; 179 employees with a 59.9% YoY decline; recognized leader in managed security by ISG Provider Lens; part of Stefanini Group, founded in 2016, headquartered in São Paulo.
CyberBrain Consulting
CyberBrain Consulting is a Brazil-based security and investigations company founded in 2019, with 1 employee. They specialize in cybersecurity solutions, including information security diagnostics and penetration testing services, aimed at enhancing organizational security processes and awareness. Their web presence is limited, with 288 monthly visits, reflecting a niche market focus.
ISH Tecnologia
Brazil-based IT services and consulting company founded in 1996; 611 employees; $25M-$50M revenue; offers cybersecurity services including penetration testing; operates in five states; recognized as one of Brazil's fastest-growing IT firms; global rank ~1.65M, local rank 117,415; employer rating 4.1/5 based on 411 reviews.