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Offensive security assessments

Firewall Assessment Fundamentals

Firewall security assessment evaluates whether a firewall's rules, segmentation, and

Why it matters

Firewall security assessment evaluates whether a firewall's rules, segmentation, and inspection actually enforce the intended security policy. A firewall is only as good as its ruleset and the architecture around it.

How we test it

Our operators follow a structured checklist for this topic, adapted to your API surface and authentication model.

Testing approach

  • Ingress filtering: what can reach internal services from outside.
  • Egress filtering: what internal hosts can send out (often weak, and key to
  • Segmentation: whether network zones (DMZ, internal, management) are truly isolated.
  • Inspection: whether the device decodes and blocks malicious traffic, or just filters
  • Identify the firewall: fingerprint via banners, TTLs, error behaviour, and management interfaces
  • Note vendor and likely model
  • Map the ruleset behaviourally: scan from multiple source zones to learn which ports/protocols are permitted where
  • Test segmentation: from each zone, attempt to reach hosts in others; segmentation gaps are common and high-impact

What we look for

  • Ingress filtering: what can reach internal services from outside.
  • Egress filtering: what internal hosts can send out (often weak, and key to
  • Segmentation: whether network zones (DMZ, internal, management) are truly isolated.
  • Inspection: whether the device decodes and blocks malicious traffic, or just filters
  • Identify the firewall: fingerprint via banners, TTLs, error behaviour, and management interfaces
  • Note vendor and likely model
  • Map the ruleset behaviourally: scan from multiple source zones to learn which ports/protocols are permitted where
  • Test segmentation: from each zone, attempt to reach hosts in others; segmentation gaps are common and high-impact