Penetration Testing

Expert-led security testing that finds vulnerabilities before attackers do - giving you confidence in your defences and evidence for compliance.

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Challenges we solve

Cyber threats are evolving constantly. Without regular, thorough security testing, your organisation is exposed to risks that could have been prevented.

Unknown vulnerabilities in your estate

Your applications, infrastructure, and networks may harbour critical security flaws that automated scanners miss. Without manual, expert-led testing, these vulnerabilities remain hidden until an attacker exploits them.

Compliance and regulatory pressure

Regulations like PCI DSS, ISO 27001, and Cyber Essentials require regular penetration testing. Your team needs reliable, accredited testing to satisfy auditors and maintain certifications.

Lack of in-house security expertise

Hiring and retaining skilled penetration testers is expensive and competitive. Your internal team may lack the specialist offensive security skills needed to simulate real-world attack scenarios.

No clear picture of your risk posture

You need actionable intelligence about your security weaknesses - not just a list of CVEs. Without context-aware reporting, it’s difficult to prioritise remediation and demonstrate progress to the board.

What is Penetration Testing?

Proactive, expert-led security assessments that go beyond automated scanning.

Claranet’s Penetration Testing service delivers thorough, manual security assessments of your applications, infrastructure, and networks. Our CHECK and CREST-accredited testers use the same techniques as real-world attackers to identify vulnerabilities, assess their exploitability, and provide clear, prioritised remediation guidance.

Every engagement begins with a detailed scoping process. We work with you to define the scope, objectives, and rules of engagement through a formal Statement of Work. Testing combines automated vulnerability assessment with extensive manual exploitation techniques, ensuring we find the issues that scanners alone cannot detect.

You receive a comprehensive report that goes beyond technical findings. Each vulnerability is rated using the industry-standard CVSS scoring framework, with an executive summary for senior stakeholders, graphical risk overviews, detailed technical analysis including exploitation paths, and specific remediation recommendations your team can act on immediately.

Key benefits

CHECK and CREST accredited testers
CVSS-scored vulnerability reporting
Combined automated and manual testing
Executive and technical reporting
Encrypted, secure communications throughout

Credentials

Trusted by organisations across the UK for offensive security.

1,000+ Penetration tests delivered annually

CHECK NCSC-approved testing provider

CREST Accredited penetration testing

20+ Years of security testing experience

QA All reports peer-reviewed before delivery

What we test

Comprehensive coverage across your entire attack surface.

Web Applications

OWASP-aligned testing of web apps, APIs, and portals.
Mobile Applications

iOS and Android app security including data storage and API calls.
Infrastructure

Internal and external network infrastructure testing.
Wireless Networks

Wireless security assessment including rogue access point detection.
Red Team Exercises

Goal-oriented adversary simulation across your entire organisation.
Social Engineering

Phishing, vishing, and physical security testing of your people
Device & Build Reviews

Configuration and hardening reviews of servers, endpoints, and appliances.

Technical capabilities

A rigorous, methodology-driven approach to finding and reporting vulnerabilities.

Automated Vulnerability Assessment

Industry-leading scanning tools identify known vulnerabilities, misconfigurations, and outdated software across your environment. This forms the baseline that our manual testing builds upon.

Manual Exploitation & Testing

Expert testers go beyond automated scanning to discover logic flaws, chained vulnerabilities, and business logic issues. Manual testing uncovers the critical findings that tools cannot detect.

CVSS Vulnerability Scoring

Every vulnerability is rated using the Common Vulnerability Scoring System, providing a standardised risk rating. Findings include exploitation paths, impact assessment, and likelihood analysis.

Comprehensive Reporting

Reports include an executive summary, graphical risk overview, detailed vulnerability analysis with screenshots and proof-of-concept, plus specific remediation guidance. All reports undergo QA peer review. Reports delivered via a secure portal.

Retesting & Verification

After you’ve remediated findings, we retest to verify that vulnerabilities have been properly fixed. Retesting is included as part of the engagement, giving you documented evidence of your improved posture.

Secure Engagement Process

All communications and data transfers use encryption. Formal scoping, Statement of Work, and rules of engagement ensure testing is controlled, safe, and aligned with your risk appetite.