External Penetration Test

Systematic assessment of your external attack surface. We test your publicly accessible systems using real attacker methods.

An external penetration test assesses the security of all IT systems directly accessible from the internet. These include web applications, websites, APIs, mail servers, VPN gateways, remote desktop services, external management interfaces, and other publicly exposed services. These systems form a company’s digital facade – and are therefore a preferred target for attackers.

The goal of an external penetration test is to analyze these exposed components realistically from the perspective of an external, anonymous attacker. The following areas are systematically assessed:

  • Whether publicly accessible systems are correctly configured
  • Whether known vulnerabilities (e.g., in web servers, frameworks, or login mechanisms) can be exploited
  • Whether sensitive information is accessible without authorization
  • Whether vulnerabilities enable unauthorized connections to the internal network
  • Whether authorized access points such as VPN, VDI, or RDP are securely implemented

An external penetration test simulates real attack scenarios – from target system reconnaissance through automated vulnerability scanning to targeted manual attacks, such as bypassing authentication or exploiting flawed access controls.

CORPORATE PERIMETER Webserver :443 Mailserver :25/587 VPN :1194 DNS API Database Firewall ON-PREMISE CLOUD Azure / AWS IaaS / PaaS Cloud Storage S3 / Blob Identity Provider (Entra ID) 3RD PARTY / SAAS M365 Mail / Teams CRM / ERP Salesforce etc. Collaboration / File Sharing Pentester (external) HTTPS SMTP OpenVPN Port Scan Cloud APIs OAuth / SSO EXTERNAL

Typical risks uncovered during external tests include: outdated systems, missing security updates, misconfigured firewalls, unprotected APIs, weak authentication, and unencrypted transmission of sensitive data.

Such tests are especially relevant for companies providing digital services – in areas such as e-commerce, financial services, healthcare, the public sector, or Industry 4.0. But smaller organizations with individual cloud services or a simple web presence also benefit from this type of security assessment, enabling them to identify and address attack risks early.

Contact us for a consultation and further information.