pfSense Firewall Configuration & Hardening · Hacking Project

Design, configure, and harden a segmented, least-privilege firewall that enforces defense-in-depth and secure remote access.

**The problem**
Flat home and SMB networks with default-permit firewalls let a single compromised device reach everything — IoT, management interfaces, and sensitive servers alike. Many practitioners have never designed segmented VLANs, least-privilege firewall rules, VPN access, or IDS integration on a real firewall. Misconfigured or unhardened perimeter devices are themselves a top breach vector.

**What you'll build**
Deploy pfSense (or OPNsense) as the network gateway and implement defense-in-depth: VLAN segmentation, least-privilege rule sets, GeoIP/threat-feed blocking (pfBlockerNG), a WireGuard/OpenVPN remote-access tunnel, Suricata inline IDS/IPS, and hardened management access with MFA. Document the architecture against Zero Trust principles and validate segmentation with cross-VLAN testing.

**Objective** — Design, configure, and harden a segmented, least-privilege firewall that enforces defense-in-depth and secure remote access.

**Expected outcome** — A hardened pfSense deployment with documented VLAN/firewall architecture, VPN, threat blocking, and a hardening/validation report.

**Difficulty** — Beginner-to-Intermediate — the GUI lowers entry, but VLAN design, rule ordering, and Zero Trust segmentation require networking maturity.

**Primary category** — Network Security / Perimeter Defense; Secondary = Infrastructure Security, IAM (VPN access), SOC

**Security domains** — Primary = Blue Team; Secondary = Cloud Security (hybrid networking), GRC (control implementation), Incident Response

**Technical focus** — Firewall rule design, network segmentation/VLANs, NAT, VPN configuration, IDS/IPS integration, GeoIP/threat blocking, device hardening, secure remote access, Zero Trust segmentation

**Core technologies** — Languages: Bash, minimal scripting; Frameworks/Libraries: pfSense/OPNsense, WireGuard, OpenVPN; Security Tools: pfBlockerNG, Suricata/Snort, nmap (validation); Cloud/Infra: managed switch with VLANs, virtualized firewall (Proxmox/ESXi) or appliance; AI/Data: firewall/flow logs to SIEM; Databases: N/A (config-centric)

**Where it's valued** — SMB/MSP, enterprise IT, managed network services, any regulated environment needing segmentation

**Careers it builds toward** — Network Security Engineer, Firewall Administrator, Security Engineer, Network Administrator, Infrastructure/SysAdmin moving into security

**Framework alignment**
• MITRE ATT&CK: Mitigates Lateral Movement/Remote Services (T1021), Exploitation of Remote Services (T1210), Network Service Discovery (T1046), Exfiltration Over C2 (T1041), Non-Application/Non-Standard Port C2 (T1571); implements Network Segmentation (mitigation M1030) and Filter Network Traffic (M1037)
• NIST CSF 2.0: Protect (PR.IR infrastructure resilience/segmentation, PR.AA authentication for VPN, PR.PS platform hardening), Detect (DE.CM via integrated IDS); aligns with NIST 800-207 Zero Trust
• OWASP: N/A (network layer)
• CIS Controls v8: 4 (Secure Configuration), 12 (Network Infrastructure Management), 13 (Network Monitoring and Defense), 6 (Access Control Management)

**Innovation** — Existing Idea — foundational and universally valuable, but not novel; a rigorous Zero Trust segmentation design elevates the portfolio value. Scores: Innovation 3/10, Startup 2/10, Enterprise-Readiness 8/10, Patent = No.