Internal Penetration Testing

The Evolution of Internal Threats

The traditional concept of a hardened perimeter protecting a soft internal network no longer applies in modern enterprises. With the rise of hybrid work environments, cloud services, and interconnected systems, the distinction between internal and external networks has blurred significantly. This evolution requires a sophisticated approach to internal security testing that accounts for both traditional and emerging attack vectors.

A Recent Critical Discovery

Our team recently conducted an internal penetration test for a major financial institution that perfectly illustrates the importance of thorough internal testing. Starting with standard user credentials, we discovered a chain of vulnerabilities that could allow an attacker to elevate privileges to domain administrator within hours. The attack path involved a combination of misconfigured group policies, weak service account passwords, and unpatched internal systems.

The most concerning aspect wasn’t any single vulnerability, but how these issues could be chained together. A compromised user account could exploit a local privilege escalation vulnerability to gain system access, leverage that access to extract service account credentials, and ultimately use those credentials to compromise the entire Active Directory domain. This finding led to immediate remediation efforts that significantly improved the organization’s security posture.

Active Directory Security Assessment

In most modern enterprises, Active Directory forms the backbone of internal security. Our testing methodology includes comprehensive assessment of Active Directory configuration, examining trust relationships, group policies, and delegation settings. We analyze password policies, service account security, and privileged access management implementations, identifying potential paths to domain compromise.

Lateral Movement and Privilege Escalation

Understanding how attackers move laterally through a network is crucial. Our team examines common lateral movement techniques, including pass-the-hash attacks, token manipulation, and abuse of trust relationships. We evaluate how effectively your security controls detect and prevent such movement, testing everything from network segmentation to endpoint protection solutions.

Data Access and Protection

Beyond system compromise, we examine how data is protected within your internal network. This includes evaluating file share permissions, database security, and access control implementations. Our team identifies sensitive data repositories and demonstrates how an attacker might access this information through various attack paths.

Internal Network Segmentation

Effective network segmentation is crucial for limiting the impact of potential breaches. Our assessment examines how well your network segments are isolated, testing boundary controls and identifying potential bypass methods. We evaluate both traditional VLAN segregation and modern micro-segmentation implementations, ensuring they provide effective security boundaries.

Modern Workplace Security

With the rise of hybrid work environments, internal network security has become more complex. We evaluate how remote access solutions, VPN configurations, and cloud service integrations affect your internal security posture. This includes testing how effectively your security controls adapt to various work scenarios while maintaining strong security boundaries.

Technical Control Effectiveness

We evaluate the effectiveness of technical security controls, including:

• Endpoint Detection and Response (EDR) solutions
• Data Loss Prevention (DLP) systems
• Security Information and Event Management (SIEM) platforms
• Network Access Control (NAC) implementations
• Privileged Access Management (PAM) solutions

Incident Response Capabilities

An important aspect of internal testing is evaluating how effectively your organization can detect and respond to internal threats. We assess logging configurations, monitoring capabilities, and alert effectiveness. This includes testing whether suspicious activities trigger appropriate alerts and whether your security team can effectively track and respond to internal threats.

Remediation and Improvement

Following our assessment, we provide detailed remediation guidance that goes beyond simple vulnerability fixes. We help organizations develop a comprehensive security improvement plan that addresses both immediate vulnerabilities and systemic issues. This includes recommendations for:

• Improving security architecture
• Enhancing monitoring capabilities
• Strengthening access controls
• Implementing security best practices
• Developing security policies and procedures