AD-SUB-10: Distinct first three octets (/24 networks) count should be retrievable
| ID | AD-SUB-10 |
| Severity | Info |
| Suite | Active Directory (on-premises) |
| Product | Active Directory |
| Feature | Sites and subnets |
| Security area | Infrastructure hardening |
| Resource type | AdSite |
| Reads from | On-premises Active Directory |
What this checks and how to fix it
Section titled “What this checks and how to fix it”Analyzing /24 network distribution provides:
- Subnet granularity: Understanding the typical subnet size in use
- Location mapping: Each /24 often represents a specific location or VLAN
- Capacity insight: How many discrete network segments exist
- Documentation: Detailed network topology information
/24 networks (254 hosts) are the most common subnet size for client networks.
Control Type
Section titled “Control Type”Operational
Security Recommendation
Section titled “Security Recommendation”- Document the purpose of each /24 network
- Align /24 boundaries with physical locations or security zones
- Plan /24 allocation to support VLAN and location requirements
- Review /24 utilization for optimization opportunities
How the Test Works
Section titled “How the Test Works”This test extracts the first three octets from all IPv4 subnets and counts the distinct /24 networks.
Related Tests
Section titled “Related Tests”Test-MtAdSubnetFirstOctetCount- Analyzes first octetsTest-MtAdSubnetFirstTwoOctetsCount- Analyzes /16 networksTest-MtAdSubnetTotalCount- Counts total subnets
Mito check. Author: soulemike. Open-source licences.
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