Web Application Penetration Testing

Web application penetration testing is a manual, CREST-accredited security assessment that identifies and exploits vulnerabilities in websites, web apps, APIs, and mobile applications. Unlike automated scanning, it uses expert-led techniques to uncover logic flaws, authentication weaknesses, injection vulnerabilities, and other issues that automated tools routinely miss.

Web applications are one of the most frequently targeted attack surfaces – they are internet-facing, handle sensitive user data, and often contain custom code that automated tools cannot fully assess. A web app pen test provides independent, evidence-based assurance that your applications are secure, helps you meet compliance requirements, and protects your users and your reputation.

At a minimum, web application penetration testing should be performed annually and after any significant change to your application – such as new features, authentication changes, API additions, or infrastructure migrations. Organisations in regulated industries such as financial services, healthcare, and e-commerce should consider more frequent testing. PCI DSS v4.0 requires penetration testing after any significant system change.

CyberLab’s consultants use a combination of industry-leading tools – including Burp Suite Pro for manual web app testing – alongside custom scripts and techniques developed in-house. Automated scanners are used as a starting point, but the majority of the assessment is manual, carried out by developer-trained consultants who understand application architecture, not just attack patterns.

Web application penetration testing should be conducted by CREST-accredited consultants with specific application security expertise. CyberLab’s team includes developer-trained testers certified to CREST CCT level, with experience across a wide range of application types, technology stacks, and regulated sectors including financial services, healthcare, and public sector.

OWASP (Open Web Application Security Project) publishes the OWASP Top 10 – the globally recognised standard for the most critical web application security risks, including injection attacks, broken authentication, and security misconfigurations. CyberLab’s web application penetration testing is aligned with the OWASP Top 10, OWASP API Top 10, and OWASP MASVS for mobile applications, ensuring your testing covers the vulnerabilities most likely to be exploited by real attackers.

A vulnerability scan uses automated tools to identify known weaknesses based on a database of existing CVEs – it is fast, broad, and useful for ongoing monitoring. A web application pen test is a manual, expert-led assessment that goes further by actively exploiting vulnerabilities, chaining weaknesses together, and testing application-specific logic that automated tools cannot assess. A vulnerability scan tells you what is exposed; a pen test tells you what an attacker could actually do with it.

Timescales depend on the complexity and scope of the application. A straightforward web application with limited functionality typically takes three to five days. Larger applications with multiple user roles, complex business logic, extensive API coverage, or mobile app components may require ten days or more. CyberLab also offers next-day testing for urgent compliance deadlines or audit requirements – speak with our team to scope your engagement.

CyberLab’s web application penetration testing covers the full range of digital application types: public-facing websites, authenticated web applications, REST and SOAP APIs, GraphQL endpoints, and iOS and Android mobile applications. Each is assessed using the relevant OWASP methodology – OWASP Top 10 for web apps, OWASP API Top 10 for APIs, and OWASP MASVS for mobile. If you have multiple application types, we can scope a combined engagement covering all of them.

The OWASP Top 10 is the globally recognised standard for the most critical web application security risks, published and maintained by the Open Web Application Security Project. It covers the vulnerabilities most frequently exploited in real-world attacks – including injection attacks, broken authentication, security misconfigurations and insecure design. CyberLab’s web application penetration testing is fully aligned with the OWASP Top 10, OWASP API Top 10 and OWASP MASVS for mobile, ensuring your test covers the vulnerabilities that matter most.

We can test in either environment, and we will discuss this during scoping. Testing in a staging environment reduces the risk of disruption to live users but may not accurately reflect the production configuration. Testing in production provides a more accurate picture of your real-world attack surface but requires careful planning around test windows and sensitive operations such as payment flows. Our consultants are experienced in working safely in production environments and will agree appropriate safeguards with your team before testing begins.

A Build Review involves evaluating the security configurations of your IT systems, ensuring they align with industry best practices and security benchmarks. This helps identify vulnerabilities and misconfigurations that could be exploited by attackers.

Build Reviews proactively identify and address security weaknesses in your system configurations, reducing the risk of breaches and ensuring your IT environment is securely configured against evolving threats.

A cyber security build review involves a systematic assessment of the security configuration applied to devices and systems within your organization’s IT environment. This includes servers, laptops, mobile devices, and network equipment such as firewalls, routers, and switches. The review evaluates the effectiveness of current security settings, identifies misconfigurations or deviations from best practices, and uncovers any weaknesses that could expose your organization to potential threats.

Build Reviews should be conducted regularly, especially after significant changes to your IT environment or systems. It’s also recommended to perform reviews annually to ensure your configurations remain secure and compliant with the latest security standards.

A Build Review should be conducted by certified security professionals with expertise in configuration management and security benchmarking. CyberLab’s team is CREST and CHECK certified, ensuring compliance with industry standards and best practices.

While Penetration Testing simulates attacks to identify exploitable vulnerabilities, Build Reviews focus on manually inspecting system configurations against security benchmarks to identify misconfigurations and hardening weaknesses before they can be exploited.

Yes, you will receive a comprehensive report that outlines the findings, categorising vulnerabilities by severity, and providing actionable recommendations to enhance your systems’ security.

CyberLab assesses configurations against CIS Benchmarks Level 1 and 2, DISA STIG (Defense Information Systems Agency Security Technical Implementation Guides) and Microsoft Security Baselines. CIS Benchmarks are globally recognised consensus-based configuration guidelines developed by the Center for Internet Security and are widely accepted as the industry standard for system hardening. Level 1 benchmarks cover essential configuration changes with minimal operational impact, while Level 2 covers more comprehensive hardening measures suited to high-security environments.

A penetration test actively attempts to exploit vulnerabilities in your systems, simulating a real attacker. A build review is a manual inspection of how your systems have been configured, comparing current settings against security benchmarks without attempting active exploitation. The two services are complementary – a build review identifies hardening weaknesses before a pen test, and a pen test validates whether remaining weaknesses after remediation can actually be exploited. Many organisations run both as part of a structured security programme.