Network Penetration Testing
Network infrastructure vulnerability assessment and penetration testing for perimeter and internal networks.
Network infrastructure forms the critical backbone of every organization's IT operations, connecting users, applications, and data across internal and external boundaries. Network Penetration Testing is a systematic evaluation of your network security controls designed to identify vulnerabilities in routers, switches, firewalls, load balancers, VPN concentrators, wireless access points, and other network devices. Our testing covers both external perimeter defenses and internal network segmentation, providing a complete picture of your network security posture from the perspective of attackers operating both outside and inside your network boundary.
Our methodology encompasses comprehensive testing across multiple attack surfaces. We begin with external testing that simulates an internet-based attacker attempting to breach your perimeter, including firewall rule enumeration, VPN gateway assessment, public-facing service exploitation, and DDoS resilience evaluation. Internal testing assumes the perspective of an attacker who has already gained a foothold — perhaps through a phishing email or compromised endpoint — and assesses your internal network security, lateral movement resistance, segmentation effectiveness, and privilege escalation opportunities. This dual perspective is essential because many organizations focus heavily on perimeter defense while neglecting internal network security, leaving them vulnerable to breaches that bypass the perimeter.
We conduct detailed evaluations of network segmentation and micro-segmentation implementations, examining VLAN configurations, ACL rules, firewall policies, and routing controls to identify bypass paths between security zones. Our wireless security testing covers WPA2/WPA3 Enterprise and PSK assessments, rogue access point detection capabilities, wireless invasion testing, and Bluetooth/BLE attack surface evaluation. VPN assessment includes protocol-level security testing (IPsec, SSL/TLS VPN, WireGuard), authentication mechanism review, split tunneling analysis, and post-connection network access controls. We also evaluate network access control (NAC) implementations including 802.1X, MAB, and guest network isolation mechanisms.
Beyond technical testing, we assess your network monitoring and detection capabilities. Our team evaluates the effectiveness of your intrusion detection and prevention systems (IDS/IPS), network detection and response (NDR) solutions, security information and event management (SIEM) correlation rules, and network traffic analysis tools. We conduct stealth assessment to determine whether our testing activities trigger alerts, providing a direct measure of your detection coverage. The output is an integrated view of both your prevention and detection capabilities, enabling you to strengthen defenses and improve your security operations center's (SOC) ability to identify and respond to network-based threats in real time.
How We Deliver
A structured methodology refined through hundreds of successful engagements.
External Perimeter Assessment
We map your entire external attack surface through internet-wide scanning and OSINT gathering, identifying all public-facing IP ranges, open ports, running services, and SSL/TLS certificate configurations. We perform banner grabbing, service fingerprinting, and version detection to identify outdated or vulnerable software. Firewall rule enumeration uses techniques like Firewalking to determine permitted and denied ports. VPN gateway testing includes protocol analysis, authentication mechanism review, and split-tunneling configuration assessment.
Internal Network Penetration Testing
Assuming an initial foothold, our testers conduct internal network scans from multiple VLAN segments to evaluate lateral movement resistance. We perform ARP/DHCP/DNS spoofing assessments, LLMNR/NBT-NS/mDNS poisoning tests, SMB relay attacks, and Active Directory enumeration. We assess the security of network protocols including SNMP, RDP, SSH, Telnet, and NFS. Privilege escalation testing targets local admin accounts, service accounts, scheduled tasks, and vulnerable kernel versions on both Windows and Linux systems.
Firewall & Segmentation Bypass Testing
We systematically evaluate your network segmentation by attempting to bypass ACLs, firewall rules, and routing restrictions between trust zones. This includes VLAN hopping (switch spoofing and double tagging), tunneling through allowed protocols (DNS, ICMP, HTTP/S), IPv6 transition mechanism abuse, and GRE/IP-in-IP tunneling. We test DMZ-to-internal segmentation, PCI network isolation, and jump server configurations. All bypass paths are documented with the specific controls that were circumvented.
Wireless & Physical Network Security
Our wireless assessment includes war-driving for SSID discovery, WPA2/WPA3 handshake capture and offline cracking, PMKID attacks, Evil Twin and KARMA attacks, RADIUS server credential testing for 802.1X networks, and captive portal bypass techniques. We also evaluate physical network security including switch port security, DHCP snooping, dynamic ARP inspection, MAC flooding, and STP manipulation. Bluetooth Classic and BLE assessments cover discovery, pairing mechanism review, and service enumeration.
Detection Evasion & Reporting
We conduct stealth assessment to gauge your network detection capabilities, using low-and-slow scanning techniques, encryption tunneling, and timing-based evasion to evaluate IDS/IPS and NDR alert generation. Findings are compiled into a prioritized report with CVSS scoring, exploitation difficulty ratings, and business impact analysis. Each finding includes detailed remediation guidance with configuration examples for major vendor platforms (Cisco, Palo Alto, Fortinet, Juniper). We provide before-and-after re-testing upon remediation completion.
What You Receive
Every engagement delivers actionable insights and tangible outcomes.
Network Security Assessment Report
Comprehensive report covering external, internal, wireless and physical network findings with CVSS scores, exploitation walkthroughs, and vendor-specific remediation.
Attack Surface Map
Visual network topology diagram highlighting discovered hosts, services, open ports, trust relationships, and identified attack paths between security zones.
Exploitation Validation
Documented proof-of-concept demonstrations for each exploited vulnerability, including command sequences, tool outputs, and extracted data samples where applicable.
External Footprint Analysis
Complete inventory of external-facing assets, SSL/TLS certificate analysis, DNS zone enumeration results, and shadow IT discovery across public cloud and ISP ranges.
Key Benefits
Partner with SecureNexGen for results that matter.
Dual Perspective Coverage
Both external and internal testing provides complete visibility into your network security from both outside-in and inside-out attack perspectives.
Detection Validation
Direct measurement of IDS/IPS, NDR, and SOC alert generation effectiveness through stealth testing techniques that simulate real attacker behavior.
Segmentation Verification
Empirical validation that your network segmentation controls actually prevent lateral movement between trust zones, with documented bypass paths identified.
Actionable Remediation
Vendor-specific configuration guidance for Cisco, Palo Alto, Fortinet, Juniper, and open-source platforms, enabling rapid and accurate fix implementation.
What's Covered
Comprehensive scope designed to leave no stone unturned.
Frequently Asked Questions
Common queries about our service delivery and process.
What's the difference between external and internal network penetration testing?
How do you test without causing network disruption?
Do you test both IPv4 and IPv6 networks?
How often should network penetration testing be performed?
What credentials and access do you need to perform the testing?
Ready to Get Started?
Contact our team to discuss your requirements and receive a tailored proposal.