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Security Testing

Guest Network Isolation

Guests should stay in the guest room.

Verification that guest wireless networks are properly isolated from production environments and sensitive resources.

Overview

Guest networks serve visitors, contractors, and BYOD devices—entities you explicitly don't trust with production access. Guest Network Isolation testing verifies that guests are actually isolated. We connect to your guest network and systematically attempt to reach production systems, proving whether your segmentation works or identifying where it fails.

What We Test

Our guest network isolation engagements cover these key areas:

VLAN segmentation between guest and production networks

Firewall rules controlling inter-network traffic

Access to internal DNS servers and name resolution

Reach to management interfaces and administrative systems

Path to sensitive network segments (finance, HR, healthcare)

Ability to communicate with other guests (isolation)

Our Approach

Isolation testing connects to your guest network and attempts everything a malicious guest might try. We test from the perspective of an attacker on guest WiFi looking for paths into production.

1

Guest Network Connection

Connect to guest network through normal onboarding process—captive portal, access code, or open access. Document the authentication experience.

2

Network Reconnaissance

Enumerate what's reachable from guest: IP ranges, DNS servers, gateways. Identify any production resources visible from guest perspective.

3

Segmentation Testing

Systematically attempt connections to production network ranges. Test common ports and protocols looking for segmentation gaps.

4

DNS Analysis

Test whether guest DNS resolves internal hostnames, potentially revealing internal infrastructure or enabling access through DNS-based attacks.

5

Guest-to-Guest Testing

Verify client isolation—whether guests can see and attack other guest devices, or whether they're properly segmented from each other.

6

Egress Testing

Test what internet access guests have—unrestricted, filtered, or proxied. Identify potential data exfiltration paths.

Common Findings

These are issues we frequently discover during guest network isolation engagements:

Production resources reachable

VLAN ACLs or firewall rules incomplete—certain production systems accessible from guest network through overlooked ports or protocols.

Internal DNS exposed

Guest network uses internal DNS servers that resolve production hostnames, revealing infrastructure and potentially enabling access.

Management interfaces accessible

Network device management interfaces, printer configurations, or other administrative systems reachable from guest network.

Missing client isolation

Guests can scan and attack other guest devices. In shared environments, this enables attacks against visitor laptops and devices.

Captive portal bypass

Guest authentication captive portal bypassable through DNS tunneling, MAC spoofing, or protocol-specific exceptions.

Common Questions

What should guests be able to access?

Typically: internet access for web and email, nothing else. Some organizations allow specific resources like guest printing. Everything beyond minimal internet should be explicitly justified and controlled.

Do you test the captive portal itself?

Yes. We test authentication mechanisms, session handling, and bypass techniques. Captive portals often have vulnerabilities that allow unauthenticated access.

What about contractor networks?

Contractor or partner networks need similar testing with appropriate access requirements. They may legitimately need more access than guests, but that access should be explicitly defined and verified.

How do we fix segmentation issues?

Typically through VLAN configuration, ACLs, and firewall rules. We document specific paths that should be blocked and can work with your network team on proper segmentation architecture.

Ready to Strengthen Your Defenses?

Schedule a free consultation with our security experts to discuss your organization's needs.

Or call us directly at (445) 273-2873