Assumed Breach Testing Providers

Assumed breach testing is a targeted security assessment that begins from the premise that an attacker has already gained initial access to the organisation's environment. Instead of spending time on initial compromise (which is covered by traditional pen testing), assumed breach testing focuses on what an attacker can achieve once inside the network.

Testers are given a starting point such as a compromised user workstation, VPN credentials, or access to a specific network segment, and then attempt to escalate privileges, move laterally through the network, access sensitive data, and reach high-value targets or crown jewel assets. This approach directly tests the effectiveness of internal security controls including network segmentation, endpoint detection and response (EDR), privilege access management, monitoring and alerting, and incident response procedures.

Assumed breach testing is highly efficient because it focuses testing time on the most impactful scenarios - the activities an attacker would perform after gaining initial access. It is particularly valuable for organisations that want to test their internal defences and detection capabilities without spending engagement time on perimeter testing. This approach is recommended by NIST and aligns with zero-trust security principles that assume breach as a starting point for security architecture.