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Website Penetration Testing

Identify vulnerabilities in your web applications with CREST-approved website penetration testing.

Best Cyber Security Company 2021

Best Cyber Security Company 2021

Best Cyber Security Company 2022

Best Cyber Security Company 2022

Crest Accreditation

What is web application penetration testing?

Web application penetration testing is a cyber security process that simulates an attack on a website or web application. By trying to exploit vulnerabilities in the application, pentesters can discover any weaknesses that real-world attackers could exploit.

Web application penetration tests are becoming increasingly important as more businesses move their applications and data online.

Why you need website penetration testing

In the digital age, web applications and their supporting infrastructure are critical to most businesses. They are crucial marketing tools which supply customers with information on the organisation’s services. They also provide valuable tools to internal teams and customers that help enhance collaboration, communication and productivity.

To fulfil this business-critical role, web applications store substantial amounts of sensitive data, including personally identifiable information (PII) about customers and commercially sensitive intellectual property or trading information. These make web applications a prime target for malicious actors.

A data breach – no matter how small – has the potential to cause significant financial, reputational and operational damage. Can your organisation afford to take the risk?

Penetration test reporting

To maximise the value gained from a penetration test, it is essential to act upon the vulnerabilities identified during an engagement. Our penetration testing service provides a detailed technical report to assist you in making these important improvements.

Our technical penetration testing reports include:

  • A succinct Management Summary with key statistical information
  • A Technical Summary covering the most important considerations
  • Full technical details of every vulnerability discovered, including the assessed impact
  • Clear vulnerability weightings to aid in prioritising remediation
  • Detailed and practical guidance for technical remediation of each vulnerability

We understand that technical reports can be difficult to consume, so ours is tailored heavily on feedback from our valued customers. Furthermore, our consultants are always available to discuss questions you may have once you have received the report.

Types of penetration testing

As well as website pentests, our team provides the following penetration testing services:

Our network and infrastructure penetration testing investigates your internal and external networks and systems for vulnerabilities. It safely simulates exploitation to demonstrate the potential impact. We have extensive knowledge of Windows and Unix environments.

Provides an in-depth review of your application’s security to ensure the data it processes is secure. We have vast experience assessing applications across iOS, Android and Windows, and mobile development frameworks such as React Native, Flutter and Xamarin.

Attempts to find misconfigurations that may expose your cloud systems and data to a malicious actor. It’s performed against environments hosted by a cloud service provider, such as Amazon Web Services (AWS), Google Cloud and Microsoft Azure.

Find out more about our full range of penetration testing services, providing a comprehensive portfolio of testing solutions for your IT systems, websites, applications and cloud infrastructure.

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Why choose Sentrium?

Our experienced and CREST-certified penetration testing team ensures we offer the required level of expertise to provide an accurate and comprehensive website penetration testing service.

Our consultants will work closely with you to determine the most appropriate testing and clarify any questions you may have.

Our communication-focused client-first approach ensures that our consultants are always on hand to answer any questions you may have. We pride ourselves on establishing and building strong and collaborative long-term relationships with our clients.

Frequently Asked Questions

Website penetration testing is designed to test the configuration of web applications and their supporting components to identify cyber security vulnerabilities that may allow for unauthorised access to sensitive information. Our security experts utilise the latest techniques and tools to simulate attacks performed by malicious actors to identify vulnerabilities.

Once the scope and any testing limitations have been agreed upon, our CREST accredited penetration testers will gather information about the target application, for example, software version information, web technologies or frameworks in use and input fields. Through this they will be identify areas of the application to target with aim of exploitation.

Our highly skilled CREST registered penetration testers perform website penetration testing to simulate attacks using the same tools and techniques used by malicious adversaries.

Authentication provides protection to application functionality and sensitive information. Authenticated web penetration testing provides a greater level of assurance as we can fully test your application’s functionality. Through this we are also able to identify additional issues such as broken access controls and authentication vulnerabilities.

Typically, an API is used to support a web application and may be hosted separately to the main web application itself. They can provide multiple endpoints that handle user requests, such as changing passwords or inserting data records. They are a critical component of web applications and their security controls should be treated as such.

This depends on the agreed upon scope of the penetration test. For example, some factors that may affect how long a penetration test takes include the size of the application under review, such as number of forms or web pages and whether any of the pen testing is performed authenticated.

This depends on the size of scope and how many days it will take to complete the penetration testing. Contact us for a quote where we can assist you with any requirements or questions you may have about your web application.

Our skilled pentesters follow strict guidelines in accordance with legal and technical standards to ensure minimal disruption to your business whilst a website penetration test is performed. If you have any concerns, please contact us as we’ll be happy to discuss them with you.

Working with a CREST-approved penetration testing provider ensures you’re in safe and experienced hands. You should have the confidence that your penetration test is thorough and comprehensive. Your provider must carry out a test that’s technically comprehensive and will adhere to information security and quality assurance requirements set by CREST.

CREST is an international not-for-profit accreditation and certification body that represents and supports the technical information security market. Companies can become a CREST member company and apply for CREST accredited services. The application requires a rigorous assessment of companies’ processes, data security and service methodologies to ensure they’re to a best practice standard.

Yes! Sentrium have achieved the standards set by CREST, and are a CREST-Approved penetration testing service provider. We’re proud to offer services that achieve CREST’s very high standard of quality and professionalism which is recognised internationally.

Once the website penetration test is complete, the pen tester(s) assigned to the project will compile a detailed report that contains the vulnerabilities that were identified, what risk they pose and recommendations on how to remediate them. Once the report has been delivered, the team will be available for a conference call to discuss the report in detail and answer any questions you may have.

What are the benefits of website pen testing?

A well-executed website pentest can help your organisation identify and fix security weaknesses before cyber attackers can gain unauthorised access to sensitive information or functionality.

Identifying the weaknesses that malicious individuals can exploit is the first step in determining how exposed your web applications are to attack.

We’ve tailored our CREST-approved web pentesting service to give you greater visibility of such flaws. Our experienced team includes technical consultants holding the CREST Certified Web Application Tester (CCT App) qualification. We conduct simulated attacks against your internal or external web applications, using their deep understanding of the tactics, techniques and procedures employed by malicious actors.

We can also conduct automated and manual penetration tests to assess API source code and backend application logic to find vulnerabilities contained within web applications.

This approach allows us to assess the security controls in place through the lens of a malicious actor and pinpoint the attack vectors they could use to compromise an application.

Our clients

Sentrium play a key role in our cyber security programme. Their team have extensive knowledge of information security and penetration testing, and have provided us with valuable insights on many occasions. We are grateful to Sentrium for their exemplary work and dedication to giving a top quality service.

Director, Manufacturing

Sentrium is a trusted partner we have used for several years. Their services are second-to-none, and the team's communication, specialised knowledge, and flexibility are commendable.

IT Manager, Software Development

Working with Sentrium Security on our penetration testing was a pleasure. Their services were comprehensive, well organised, and delivered with professionalism. They get a solid 5/5 from us.

Chief Information Security Officer (CISO), Telecommunications

Sentrium Security Ltd surpassed our expectations with professional and thorough penetration testing. They identified vulnerabilities and provided recommendations that were really easy to follow. Their commitment to a quality service is apparent, and we gladly recommend them.

Chief Operating Officer, Financial Services

We engaged Sentrium for our annual penetration testing, and the results were very good. Their team demonstrated strong technical skills and communications from start to finish. I was surprised to find that they discovered some issues that our previous company had missed! I will certainly use them again in future.

Head of IT Security, International E-commerce

Adam and James have been great to work with. Very clear communication from start to finish making the process very easy to complete whilst taking the time to understand our needs and queries.

Director, Software Development

Common web application vulnerabilities

Website pentesting can find and fix common web application vulnerabilities before cyber criminals exploit them. This helps protect your organisation from data breaches, malicious attacks and other cyber security threats.

Our expert website pentesting team will identify and attempt to exploit common vulnerabilities, including those listed in the OWASP Top 10 of application security risks and those we regularly encounter during website penetration tests. These include:


Broken access controls allow attackers to bypass an application’s authorisation processes and perform tasks as though they were privileged users. We can evaluate your API or website’s access controls to ensure that users can perform only the actions they are authorised for.

Weak configuration of TLS/SSL on a website’s or API’s supporting infrastructure can lead to encrypted data becoming compromised if not adequately secured. We can identify and address any cryptographic failures or encryption weaknesses.

Cross-site scripting (XSS), SQL injection and command injection are dangerous vulnerabilities that can lead to severe consequences, such as bypassing access controls, extracting confidential data or executing commands.

Insecure design relates to the lack of security controls integrated into the application during its development cycle. We can evaluate and test potential coding weaknesses to ensure your code is robustly designed, to prevent known attack methods.

Misconfigured web applications or security controls are common in IT environments, creating unnecessary vulnerabilities and weaknesses. We can assess and identify misconfigurations to ensure your network, systems and patches are set up correctly.

Websites often employ a wealth of functionality provided through third-party libraries and dependencies. However, outdated components are more likely to have known security vulnerabilities. We can help ensure they’re up-to-date and secure.

These failures occur when organisations haven’t properly implemented or configured their identification and authentication systems. We can identify vulnerabilities and protect against attacks that attempt to exploit these authentication weaknesses.

Software and data integrity failures can make web applications vulnerable to system compromise, malicious code or unauthorised data disclosure without adequate validation. We can assess and mitigate application security weaknesses that cause inadequate integrity verification.

Insufficient monitoring and logging of security incidents and suspicious user behaviour makes it difficult to detect attackers who have successfully exploited your web applications. We can help protect your applications against security logging and monitoring failures.

SSRF attacks involve tricking a server into making a false request to another server and using the response to gain information – or take control of – the first server. While they are difficult to detect, we can monitor your network traffic to reveal and prevent suspicious activity.

Get in touch with our experts to discuss your needs

Phone +44(0)1242 388634 or email [email protected]


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