# Internal Network Security Testing Service **URL:** https://securesys.com.tr/en/services/local-network-security-test-service ### What Is Internal Network Security Testing? Internal network security testing is a professional penetration testing service that assesses the internal network infrastructure for unauthorised access, misconfiguration, authentication weaknesses and privilege management issues. The test is performed from a genuine attacker's perspective to measure the security posture of the systems inside the organisation. ### Why Are Internal Networks at Risk? - Insider threats - Malware - Compromised user accounts - VPN access - Portable devices - Inadequate network segmentation - Active Directory misconfiguration ### What Is Tested During an Internal Network Security Test? - Active Directory - Domain controllers - File servers - Windows and Linux servers - User permissions - SMB - LDAP - DNS - DHCP - VLAN - Network segmentation - Shares - Group Policy - Local administrator accounts - Security configuration ### The Attack Chain That Starts on the Internal Network Many organisations treat the internal network as a safe environment used only by employees. Yet when recent cyber incidents are examined, a significant proportion of attacks progress through the internal network once initial access has been achieved. The attacker's goal is rarely a single user machine. Initial access is only the starting point. The real objective is to study the security controls inside the network, reach further systems, obtain privileged accounts and put critical information assets at risk. Insufficient network segmentation, users and administrators holding more rights than they need, misconfigured Active Directory policy, insecurely configured file shares or weak access controls all widen the attacker's room to manoeuvre. That can mean access to further network segments, discovery of critical servers, and business-critical systems being placed at risk. Central components such as the Active Directory infrastructure, file servers, databases, application servers, virtualisation platforms and backup systems matter enormously to operational continuity. Risks to these systems affect not only information security but the continuity of business processes, service delivery and legal obligations. Internal network security testing assesses more than known vulnerabilities: network architecture, access permissions, trust relationships, segmentation, security policy and system configuration are all evaluated as a whole. The aim is to expose the weaknesses that would let an attacker progress through the network, and to analyse the business impact of those risks. Internal network security tests performed by SecureSys specialists are planned from a genuine attacker's perspective and carried out in line with international [methodology](/en/learning/penetration-testing/penetration-testing-process-and-methodology). Findings are not reported at a purely technical level; each one is assessed together with its potential impact on the organisation, its risk level and actionable remediation guidance. Organisations can therefore see their current security posture objectively and build a network that stands up better to real threats. The purpose of an internal network security test is not simply to find vulnerabilities, but to determine the risk they pose to corporate systems, critical information assets and business continuity — so that proactive measures can be taken. ### Active Directory Security Testing Active Directory sits at the centre of authentication and authorisation in a corporate network. Compromising the domain infrastructure and reaching privileged accounts is therefore one of an attacker's first objectives. SecureSys internal network security testing analyses the Active Directory infrastructure in detail, evaluating misconfiguration, weak password policy, privileged users and authentication mechanisms. ### Principal Controls Tested - Domain controller security - Active Directory configuration - LDAP security - Kerberos security - Group Policy Objects (GPO) - Domain trust structures - Privileged accounts - Service account security - AD CS configuration - BloodHound attack path analysis ### Network Discovery Network discovery is one of the first stages of an internal network security test. Active systems, servers, client devices and network services are identified to build the inventory that the security assessment rests on. The principal components examined: - Active IP addresses - Servers - Client computers - Domain controllers - Switches and routers - Printers - NAS devices - IoT devices - Open ports - Running services ### Windows and Linux Server Security The security of servers running on the internal network is critical to preventing an attacker from gaining privilege. ### Windows Server Analysis - Security updates - Local administrator rights - SMB configuration - PowerShell security - RDP configuration - Service security - Security policy ### Linux Server Analysis - SSH security - Sudo permissions - File permissions - Cron jobs - Service configuration - Patch level - Local privilege escalation risks ### SMB, LDAP and Kerberos Security The core services used in a corporate network are the components attackers target most often. SecureSys analyses the following services in depth: ### SMB - SMB signing - SMB relay - SMB enumeration - SMBv1 usage - File share permissions ### LDAP - Anonymous LDAP - LDAP signing - LDAP enumeration - LDAP channel binding ### Kerberos - Kerberoasting - AS-REP Roasting - Golden Ticket - Silver Ticket - Pass-the-Ticket ### Network Segmentation and VLAN Security Segmentation is one of the most important defensive mechanisms in internal network security. On a poorly configured network, an attacker can reach every server from a single client machine. SecureSys performs the following checks. - VLAN design - Network isolation - Server segmentation - User segmentation - Firewall rules - Access control lists - Internal network transitions - Isolation of critical systems ### Lateral Movement Techniques Once initial access is achieved, attackers work to move on to other systems inside the network. SecureSys evaluates the following techniques under controlled conditions. - PsExec - SMB - WMI - WinRM - Remote PowerShell - Scheduled tasks - RDP - DCOM - Remote service creation - Pass-the-Hash - Pass-the-Ticket The purpose is to establish the lateral movement risk inside the network and how reachable the critical systems really are. ### Privilege Escalation Analysis We analyse the paths by which local user rights could be escalated all the way to Domain Administrator. Areas examined: - Local Administrator - Domain Admin - Enterprise Admin - SID history - ACL abuse - GPO abuse - Token manipulation - Service permissions - Registry permissions - DLL hijacking ### Pass-the-Hash and Pass-the-Ticket These advanced attacks against the authentication infrastructure are used frequently in Active Directory environments. The principal scenarios tested: - NTLM hash usage - Kerberos ticket security - Hash protection mechanisms - LSASS protection - Credential Guard - Ticket reuse - NTLM relay ### Ransomware Propagation Scenarios on the Internal Network Modern ransomware does not target a single machine; it is built to spread rapidly across the corporate network. SecureSys evaluates the following scenarios under controlled conditions. - Propagation over SMB - Propagation through Active Directory - GPO abuse - Propagation via PsExec - RDP usage - Shared folders - Network drives - Access to backup servers This lets the impact of a potential ransomware attack be assessed in advance, and the necessary controls planned. ### File Server and NAS Security File servers and NAS systems hold an organisation's most critical data. SecureSys performs the following checks. - NTFS permissions - Share permissions - Anonymous access - SMB security - Snapshot configuration - NAS management interface - User authorisation - Data access policy ### Virtualisation Infrastructure (VMware / Hyper-V) Security Because virtualisation platforms host large numbers of critical systems, they are high-priority targets. Platforms analysed: - VMware ESXi - VMware vCenter - Microsoft Hyper-V - Proxmox VE The principal controls assessed: - Management interface security - Authorisation policy - Virtual network design - Snapshot management - Virtual machine isolation - Patch level ### Network Device (Switch, Router, Firewall) Security Internal network security does not end at the servers. The security of the network devices is assessed just as thoroughly. The principal components examined: - Switch configuration - Router security - Firewall rules - ACL policy - VLAN configuration - SNMP configuration - Management interfaces - SSH and HTTPS administration - Logging mechanisms ### How the Testing Process Works SecureSys internal network security tests follow a planned, controlled process in line with international penetration testing methodology. Every stage is run so that operational continuity is preserved, and all findings are verified before they are reported. **\1. Scoping** Before testing begins we [define the scope](/en/learning/penetration-testing/how-to-define-penetration-test-scope) together with the organisation. The IP ranges, servers, Active Directory structure, network segments, user permissions and critical systems to be included are identified, and the test scenarios are built around them. **\2. Network Discovery and Analysis** The internal network infrastructure is analysed to evaluate active systems, network services, operating systems, security components and network architecture. This stage establishes the potential attack surface. **\3. Assessment of Security Controls** Authentication mechanisms, user and administrator permissions, Active Directory configuration, network segmentation, file shares and system security policy are examined in detail. Identified weaknesses are verified under controlled conditions. **\4. Risk Analysis and Verification** Verified findings are assessed for their technical and operational impact. The risk level of each vulnerability is analysed, prioritised, and its likely business impact determined. **\5. Technical and Executive Reporting** Once testing is complete, all findings are reported together with technical explanations, evidence, risk levels and remediation guidance. A summary assessment is also prepared for senior management, setting out the critical risks and the priority actions. **\6. Remediation and Retest** After the vulnerabilities have been addressed, verification testing (retest) is carried out on request. This confirms that the remediation was effective and that the security posture has genuinely improved. ### Security Assessment of Your Corporate Internal Network This is a security testing service covering manual access work against the in-scope information system components on your internal networks, their analysis, the reporting of findings with recommendations, and — where requested as part of the engagement — verification of the fixes. The number of locations to be tested and the use of remote working (VPN, SD-WAN and similar) are taken into account in the assessment. Black box testing is carried out without any allowance from the security systems. White box testing refers to controlled testing in which the testing IP addresses are permitted through the security systems and background information is shared in advance. - Audit of network segmentation, VLAN policy and access control lists (ACL). - Identification of incorrect or dangerous settings in firewall, router and switch configuration. - Review of authorisation, password policy and patching on critical services such as AD, DNS and DHCP. - Lateral movement and privilege escalation attempts from inside the network. - Review of logging, monitoring, backup and incident response readiness. The SecureSys expert team performs the testing on your internal networks and delivers reports to TSE standards. Findings are provided with impact and exploitability ratings alongside actionable remediation steps; verification testing after remediation is available on request. ### Why SecureSys? An internal network security test is not something an automated scan can complete. Assessing the organisation's network architecture, Active Directory structure, authorisation mechanisms and security controls from a genuine attacker's perspective takes expertise. At SecureSys we analyse your internal network infrastructure thoroughly, using methodologies aligned with international standards and experienced penetration testers, and we assess not only the vulnerabilities themselves but the business risk they create. **Competence under TSE TS 13638** Penetration tests are performed by specialists qualified under the TSE TS 13638 standard, in line with internationally accepted methodology. **International Testing Methodologies** Our testing is planned and executed in line with PTES (Penetration Testing Execution Standard), NIST SP 800-115, the OWASP Testing Guide and the MITRE ATT&CK framework. **Real Attack Scenarios** Internal network security is assessed through controlled, realistic attack scenarios rather than vulnerability scans alone. Network segmentation, user permissions, [Active Directory security](/en/services/ad-microsoft-security-solutions) and access controls are analysed technically. **Risk-Driven Assessment** Every finding is prioritised not only on technical grounds but against business continuity, data security, operational impact and regulatory compliance. **Technical and Executive Reporting** At the end of the test we produce a detailed findings report for technical teams and an [executive summary](/en/learning/penetration-testing/what-a-penetration-test-report-contains) setting out the business impact of the risks, their priority and the recommended actions. **Remediation and Retest Support** Technical advice is available while the findings are being addressed. On request, the fixes are tested again through verification work so the effectiveness of the measures taken can be confirmed.