Network penetration testing

Comprehensive network penetration tests from our certified security experts.

Trusted penetration testing services

CREST approved
PEN TEST approved
Offensive Security OSCP
ISO 27001 Certified
Cyber Essentials Certification
Cyber Essentials Plus Certification

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Penetration testing network & infrastructure security from Bulletproof

Internal & External Network Pen Testing

Internal and external network security testing gives you complete visibility over your infrastructure.

Crest Certified Security Experts

Our ethical hacking and network security testers are independently qualified by industry-recognised certification bodies such as CREST.

Modern Data Driven Platform

Our intuitive software uses a data driven dashboard to prioritise test results and provide key remediation guidance.

Continuous Automated Protection

Discover new security flaws and protect your business 24/7 with automated scans for continuous security.

What is network penetration testing?

What is network penetration testing?

Network or infrastructure penetration testing is a hands-on ethical hacking and network defense assessment that evaluates the security of your business network and system infrastructure. It tests internal and external networks, analysing infrastructure security for misconfigurations and design flaws, and to assess the effectiveness of network security controls.

Network penetration testing services assess vulnerabilities and technical misconfigurations within a controlled environment to attempt to exploit weaknesses and offer remediation advice for strengthening network security.

How does network pen testing work?

How does network pen testing work?

Network penetration tests are carried out with an authorised simulated attack on your network to identify vulnerabilities and assess the effectiveness of security controls. The goal of network pen testing is to help you find and prioritise your security flaws before they’re discovered and exploited by a cyber criminal.

Bulletproof’s CREST-certified penetration testers use the same tactics, techniques and procedures as real-world hackers to simulate a breach in a controlled testing environment. Penetration tests are in high demand from business of all sizes and sectors and form the basis of any cyber security strategy.

Benefits of network pen testing

Benefits of network pen testing

Compromised data and systems damaged from a cyber attack can quickly lead to financial and reputational damage that’s often hard to recover from. Exploiting vulnerabilities in a controlled environment through CREST-certified network and infrastructure pen testing allows you to see where your security defences are failing and helps you prioritise improvements.

  • Uncover vulnerabilities and poor security controls
  • Exploit network security flaws in order to understand the full risk
  • Expose insecure functionality in your networks and logic flaws
  • Forms the basis of any cyber security strategy
  • Meet compliance requirements, including PCI DSS, GDPR and more

We know the threat landscape is dynamic and constantly evolving which is why we offer 12-months of free vulnerability scanning with every penetration test package.

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Internal vs External Network Penetration Testing

External and internal network penetration testing provide two different models of what an attacker could damage within your network. Bulletproof recommends a blended test with elements of internal and external network security testing.

Internal Pen Tests

Internal Pen Tests

Internal network penetration testing can assess your more vulnerable internal network infrastructure. It’s usually a more in-depth test that models what an attacker could achieve if they were to get direct access to your internal network.

External Pen Tests

External Pen Tests

External network penetration testing determines how easily your system can be breached with little to no information provided up-front. Penetration testers start without any user privileges to internal systems.

Highlighting the most common vulnerabilities

Bulletproof penetration testers are all experienced ethical hackers with a wide knowledge of different network and infrastructure technologies. They use their insight and ingenuity to discover security flaws in your organisation. Here are the Top 10 most common internal & external network vulnerabilities we find:

  1. SSL Misconfigurations
  2. Missing HTTP Security Headers
  3. Outdated Website Libraries/Components
  4. SMB Signing not Required
  5. Excessive Information Disclosure
  6. Unnecessary Open Services
  7. Host Header Injection
  8. Outdated and Unsupported Third Party Software
  9. SSH Misconfiguration
  10. Click Jacking

of network vulnerabilities are easily fixed

2 in 10

of these will be exploited by cyber criminals

Network penetration test methodology

Bulletproof follows industry standard best practices for our penetration testing methodology

Scope definition & pre-engagement interactions

Based on your defined goals, we’ll work with you to develop a tailored testing strategy.

Intelligence gathering & threat modelling

In this reconnaissance stage, our experts use the latest groundbreaking techniques to gather as much security information as possible about the network and infrastructure in the scope.

Vulnerability analysis

This is where our network penetration testers get testing. Using the latest tools and sector knowledge, we’ll uncover what’s making your critical assets vulnerable and at risk from attack.


Using a range of custom-made exploits and existing software, our network penetration testers will test all external and internal-facing systems without disrupting your business.


The team will determine the value of the compromised targets by trying to elevate privileges and pivot to other systems and networks if you are looking to understand the full impact of the threat. All compromised systems will be thoroughly cleaned of any scripts.


Our security team will produce a comprehensive report with their findings. Once received, we’ll invite you for a collaborative read through. You’ll have the opportunity to ask questions and request further information on key aspects of your test.

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Network pen testing FAQs

After our team of experts has completed network penetration testing, you will receive a comprehensive report in our modern dashboard-driven portal. As well as prioritising the discovered threats, we include key remediation advice to help speed up your remediation efforts.

Our network pen test reports include:

  • All risks based on the current server/ application setup/configuration
  • Vulnerabilities and running services for the servers and applications
  • What has been done to exploit each security issue
  • Remediation steps
  • Near-term and long-term actions

All testing scopes are specific to your organisation so please use the above as a guide.

Testing can be performed against a non-production replica of your live environment, such as a UAT/QA environment, to ensure no risk to your live services. If testing against production is unavoidable, we can coordinate our testing activities to minimise the impact. You can also specify things like no denial of service (DoS), meaning tests will have a negligible impact on your day-to-day operations.

Standard best practices recommend regular cyber security assessments and penetration tests are a key part of this. The ramifications of security breaches can result in severe financial and reputational losses. Our network pen testing experts will identify the risks posed to your business and the report helps create a comprehensive plan to strengthen your cyber resilience. In as little as 3 days (depending on scope) and with minimal disruption to your business, you’ll know how to stay ahead of the hackers.

  • Small apps, networks, cloud systems: 2-3 days
  • Medium apps, networks, cloud systems: 5-10 days
  • Larger apps, networks, cloud systems:10 days+

All tests are tailored to you so use this as a guide.

Whilst we do not offer free retesting, we do offer 12-month vulnerability scanning.

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