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External Network Penetration Testing

Examines your organisation from an internet attacker's perspective, mapping internet-facing systems and safely demonstrating real impact.

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What is an external network penetration test?

An external network penetration test examines your organisation from an internet attacker’s perspective. It maps your internet-facing systems and attempts to identify and exploit vulnerabilities using the same methods a real threat actor would, so you can see your true external attack surface.

What we test

  • Asset discovery: identifying IP ranges, subdomains, exposed services, ports and forgotten systems still reachable from the internet.
  • Vulnerability assessment: evaluating services for known vulnerabilities, misconfigurations and weak settings, with exploitation carried out safely to demonstrate real impact.
  • Remote access infrastructure: testing VPN and remote access systems for known vulnerabilities, weak authentication and access control failures.
  • Email security: reviewing SPF, DKIM and DMARC to assess domain spoofing and phishing risk.
  • SSL/TLS configuration: checking for proper encryption settings, the absence of weak cipher suites, and valid certificates.
  • DNS and subdomain review: looking for misconfigured or abandoned subdomains vulnerable to takeover.
  • Breached credential verification: checking whether your credentials appear in public breach data or infostealer logs.

Who needs an external network penetration test?

  • Organisations with internet-facing systems such as websites, VPNs or mail servers.
  • Teams that need ISO 27001 or PCI DSS compliance.
  • Businesses launching new public infrastructure.
  • Anyone wanting a regular, at least annual, assessment of their external exposure.

What the process looks like

Testing runs remotely from a black-box starting point, using only publicly available information. The scope is confirmed in writing beforehand, testing typically spans two to four days, and the report includes severity ratings, plain-language explanations, and specific remediation guidance, along with a summary of the external attack surface we mapped.

Retesting

A retest after remediation confirms the issues are resolved.