In order to manage threats to the enterprise and adhere to compliance regulations, financial institutions must have a comprehensive security strategy that can battle both internal and external threats.
Most organizations consider external penetration tests (EPT) to be a primary weapon in their security arsenal, and perform the tests at regular intervals. EPTs are conducted from a hacker’s point of view, mimicking real-world methods a hacker would use to exploit vulnerabilities in a network, compromise security controls, and access confidential data.
Although EPTs yield extremely valuable information, an organization can’t properly assess their network’s risk exposure or the likelihood that an existing vulnerability may be compromised without testing the internal perimeter in a similar manner.
An internal penetration test (IPT) is performed to exploit vulnerabilities that exist behind the firewall and assess the impact that a successful compromise would have on the system.
Depending on what systems and controls an organization wishes to evaluate, internal penetration tests can be conducted either from a hacker’s point of view or from the vantage point of a malicious employee.
Examples of scenarios that call for conducting an internal penetration test from a hacker’s point of view include:
- Evaluating the likelihood and potential impact of an attack via a rogue access point prior to deploying an extensive wireless system; and
- Assessing the risks associated with allowing third-party vendors to access restricted network resources.
An IPT performed from the vantage point of a “rogue user” (malicious employee) usually involves allowing the tester to have a standard network account and the same network privileges as a typical employee.
From this level of access, the objective of the test is to determine how far privileges can be escalated, as well as what confidential information may be insufficiently protected. This practical approach resembles a real-world scenario that demonstrates how a typical employee can use relatively low-tech means to access and exfiltrate sensitive data.
An IPT essentially picks up where external tests leave off, allowing the organization to gain a more complete view of its security posture. IPTs also help the organization fortify its internal security by identifying security gaps caused by improper configurations, file permissions, excessive user privileges and access levels, methods of exfiltrating confidential information outside the perimeter, and ways users can circumvent technical controls.
Just as important, testing the internal systems will help validate that the existing controls actually work as intended.