| name | network-infrastructure-pentest |
| description | Network-layer security assessment covering segmentation validation, service enumeration, firewall rule analysis, protocol attacks, and infrastructure exposure testing.
|
| applyTo | **/*.{conf,cfg,rules,acl,tf,hcl,yaml,yml,json,xml,nmap} |
Network Infrastructure Pentest
Purpose
Assess network-layer security: validate segmentation, test firewall rules, enumerate exposed services, analyze routing and switching security, and identify infrastructure-level attack paths. Complements application-layer skills by testing the network foundation that applications depend on.
Triggers
- Network infrastructure authorized for testing
- Recon analysis identifies open ports or exposed services
- User requests network segmentation validation
- Firewall rules or network ACLs available for review
- VPN, remote access, or edge network in scope
Required Inputs
| Input | Description | Required |
|---|
governance_context | Active engagement governance record | Yes |
target_ranges | IP ranges, subnets, VLANs in scope | Yes |
network_diagrams | Network topology, firewall rule sets (if available) | Recommended |
access_point | Where testing originates (external, internal, DMZ, VPN) | Yes |
constraints | Rate limits, no-DoS rules, testing windows | Recommended |
Workflow
-
Scope Verification — Confirm IP ranges, ports, and testing approach are authorized. Note testing windows and rate constraints.
-
Network Discovery & Service Enumeration
- Host discovery (ICMP, TCP SYN, ARP on local segment)
- Port scanning: TCP (SYN, connect), UDP (top 1000+)
- Service version detection and banner grabbing
- OS fingerprinting
- Map: IP → hostname → service → version → state
-
Network Segmentation Validation
| Test | Method | Risk if Failing |
|---|
| VLAN isolation | Attempt cross-VLAN communication | Lateral movement between zones |
| DMZ → Internal | Test connectivity from DMZ to internal subnets | DMZ compromise reaches internal |
| User → Server | Test access from workstation segment to server management | Unauthorized server access |
| Guest → Corporate | Test guest network access to corporate resources | Untrusted device access |
| Dev → Prod | Test access from development to production networks | Dev compromise reaches production |
| Internet → Internal | Test for unfiltered inbound access | Direct external attack |
| Internal → Internet | Test egress filtering (DNS, HTTP, ICMP, raw IP) | Data exfiltration channels |
-
Firewall Rule Analysis
- Review rule sets for overly permissive rules (any/any)
- Check for shadowed rules (rules that never match)
- Identify rules allowing management protocols from untrusted zones
- Check default deny policy (implicit deny at bottom)
- Review logging configuration on deny/drop rules
- Test stateful vs stateless handling
- Check for firewall bypass via fragmentation or protocol manipulation
-
Service-Specific Testing
| Service | Port(s) | Key Tests |
|---|
| SSH | 22 | Auth methods, weak ciphers, key-based vs password, banner info |
| RDP | 3389 | NLA enabled, encryption level, BlueKeep-class vulns |
| SMB | 445 | Null session, guest access, signing, EternalBlue-class vulns |
| SNMP | 161/162 | Community strings (public/private), SNMPv3 vs v1/v2c |
| DNS | 53 | Zone transfer, cache poisoning, open resolver |
| LDAP | 389/636 | Anonymous bind, unencrypted LDAP (389 vs 636) |
| FTP | 21 | Anonymous access, cleartext credentials |
| Telnet | 23 | Cleartext protocol, credential sniffing |
| IPMI | 623 | Cipher zero, default credentials, hash disclosure |
| Database | 3306/5432/1433/27017 | Default creds, unauthenticated access, public exposure |
| VNC | 5900+ | No auth, weak auth, CVEs |
| Redis | 6379 | No auth, command execution |
| Elasticsearch | 9200/9300 | No auth, data exposure |
| Kubernetes API | 6443/8443 | Anonymous access, misconfigured RBAC |
-
Protocol-Level Attacks (within scope)
- ARP spoofing / poisoning (local segment only)
- LLMNR/NBT-NS/mDNS poisoning (for credential capture)
- DHCPv6 attacks (if IPv6 enabled)
- VLAN hopping (switch spoofing, double tagging)
- STP manipulation (topology change)
- DNS spoofing/rebinding
- WPAD abuse
- IPv6 attacks on IPv4-only networks (if IPv6 unfiltered)
-
VPN & Remote Access
- VPN endpoint enumeration and version fingerprinting
- Test for known CVEs in VPN appliances (Pulse Secure, Fortinet, Cisco, etc.)
- Check for split-tunnel vs full-tunnel configuration
- Test VPN authentication mechanisms
- Check for post-auth network access controls
- Review logging of VPN connections
-
Wireless Assessment (if in scope)
- Enumerate SSIDs and encryption types
- Test WPA2/WPA3 configuration strength
- Check for WPA2-Enterprise certificate validation
- Detect rogue access points
- Test captive portal bypass
- Check wireless network isolation from wired
-
Infrastructure Device Security
- Router/switch management interface exposure
- Default credentials on network devices
- SNMP community string testing
- Firmware version and known CVEs
- Management protocol security (SSH vs Telnet, HTTPS vs HTTP)
- Logging and monitoring configuration
-
Classify & Route — Per severity-matrix.md, route to bug-bounty-triage
Allowed Actions
- Scan authorized IP ranges and ports
- Enumerate services and versions
- Test network segmentation by attempting cross-zone communication
- Test firewall rules with crafted packets
- Attempt authentication to exposed services with default/known credentials
- Capture network traffic on authorized segments
- Test protocol-level attacks within authorized scope
- Analyze firewall rule sets provided by client
- Test VPN and remote access security
Forbidden Actions
- Scan or probe IP ranges outside authorized scope
- Perform sustained denial of service attacks
- Disrupt network infrastructure (routing changes, spanning tree attacks that cause outages)
- Intercept traffic of users not part of the assessment
- Deploy persistent network implants
- Attack upstream ISP or transit infrastructure
- Modify routing tables, VLAN configurations, or firewall rules without authorization
Output Format
### [FINDING-ID]: [Title]
| Field | Value |
|-------|-------|
| **Severity** | [S1-S5] |
| **Confidence** | [C1-C4] |
| **Status** | Suspected / Confirmed |
| **Category** | [CWE / Network] |
| **Affected Target** | [IP, hostname, subnet, device] |
| **Service** | [service:port] |
#### Issue Summary
[Description of network-level vulnerability or misconfiguration]
#### Evidence
\```
[Scan output, traffic capture, authentication result — IPs may be included per scope]
\```
**Reproduction Steps:**
1. [From testing position X]
2. [Run scan/test command]
3. [Observe result]
#### Impact
[Unauthorized access, lateral movement, data interception, infrastructure compromise]
#### Remediation
[Firewall rule change, service configuration, segmentation fix, patching]
#### Validation Notes
[Re-scan after fix, verify segmentation, test firewall rules]
References
references/severity-matrix.md — Severity classification
references/secrets-and-config-checklist.md — Service configuration
references/tool-recommendations.md — Network testing tools