MON-25: De-Militarized Zone (DMZ) Monitoring
Mechanisms exist to monitor De-Militarized Zone (DMZ) network segments to separate untrusted networks from trusted networks.
Renumbered: Formerly NET-08.1 in SCF 2025.4.
Control Question: Does the organization monitor De-Militarized Zone (DMZ) network segments to separate untrusted networks from trusted networks?
General (14)
| Framework | Mapping Values |
|---|---|
| AICPA TSC 2017:2022 (used for SOC 2) (source) | CC6.6 |
| IEC 62443-3-3 2013 | SR 1.13 |
| ISO 27002 2022 | 8.20 |
| ISO 27017 2015 | 13.1.1 |
| ISO 27018 2025 | 8.20 |
| NIST 800-171 R3 (source) | 03.13.01.b |
| NIST 800-171A R3 (source) | A.03.13.01.b |
| PCI DSS 4.0.1 (source) | 1.2.1 1.2.3 1.2.4 1.2.5 1.2.6 1.2.7 1.2.8 1.3 1.3.1 1.3.2 1.3.3 1.4 1.4.1 1.4.2 11.4.5 11.4.6 12.5.2 A1.1.4 A3.2.1 A3.2.4 |
| PCI DSS 4.0.1 SAQ A-EP (source) | 1.2.1 1.2.3 1.2.4 1.2.5 1.2.6 1.2.7 1.2.8 1.3.1 1.3.2 1.3.3 1.4.1 1.4.2 11.4.5 |
| PCI DSS 4.0.1 SAQ B-IP (source) | 1.2.3 1.2.5 1.2.6 1.3.1 1.3.2 1.3.3 1.4.2 11.4.5 |
| PCI DSS 4.0.1 SAQ C (source) | 1.3.1 1.3.2 1.3.3 11.4.5 |
| PCI DSS 4.0.1 SAQ C-VT (source) | 1.3.1 1.3.2 1.3.3 |
| PCI DSS 4.0.1 SAQ D Merchant (source) | 1.2.1 1.2.3 1.2.4 1.2.5 1.2.6 1.2.7 1.2.8 1.3.1 1.3.2 1.3.3 1.4.1 1.4.2 11.4.5 12.5.2 |
| PCI DSS 4.0.1 SAQ D Service Provider (source) | 1.2.1 1.2.3 1.2.4 1.2.5 1.2.6 1.2.7 1.2.8 1.3.1 1.3.2 1.3.3 1.4.1 1.4.2 11.4.5 11.4.6 12.5.2 A1.1.4 |
EMEA (3)
| Framework | Mapping Values |
|---|---|
| EMEA Spain CCN-STIC 825 | op.mon.1 mp.com.1 |
| EMEA EU NIS2 Annex 2024 | 6.8.2(d) |
| EMEA Saudi Arabia OTCC-1 2022 | 2-4-1-13 |
APAC (2)
| Framework | Mapping Values |
|---|---|
| APAC Australia ISM June 2026 | ISM-0637 |
| APAC New Zealand NZISM 3.9 | 19.1.14.C.01 19.1.14.C.02 |
Americas (1)
| Framework | Mapping Values |
|---|---|
| Americas Canada ITSP-10-171 2025 | 03.13.01.B |
Capability Maturity Model
Level 0 — Not Performed
Practices are non-existent, based on the inability to demonstrate an implemented and operational capability. A reasonable person would conclude the control is not being performed.
Level 1 — Performed Informally
Network Security (NET) domain capabilities are ad hoc and inconsistent. Capability criteria associated with this control may include: ▪ Policies, standards & procedures associated with NET domain capabilities provide limited coverage due to the depth and breadth of the existing documentation. ▪ Network security-related activities are decentralized (e.g., a localized/regionalized function) and uses non-standardized methods to implement secure, resilient and compliant practices. ▪ Administrative processes are used to configure boundary devices (e.g., firewalls and routers) to deny network traffic by default and allow network traffic by exception (e.g., deny all and permit by exception). ▪ Internet-facing technologies are governed no differently from internal network assets.
Level 2 — Planned & Tracked
Network Security (NET) capabilities are requirements-driven, but are not standardized across the entity (e.g., local/regional level consistency). Capability criteria associated with this control reasonably expect the following criteria to exist: ▪ Policies and standards associated with NET domain capabilities are formally documented and centrally-managed by the entity. ▪ Standardized Operating Procedures (SOP) associated with NET domain capabilities are documented and maintained by process owners. ▪ IT and/or cybersecurity personnel work with business stakeholders and process owners to appropriately scope and reasonably implement cybersecurity and data protection controls associated with NET domain capabilities to address applicable statutory, regulatory and/or contractual requirements for Technology Assets, Applications, Services and/or Data (TAASD). ▪ Network security-related controls are primarily administrative and preventative in nature (e.g., policies, standards and procedures & guidelines). ▪ Network security management may be a defined function (e.g., team or department) or assigned as an additional duty to existing IT and/or cybersecurity personnel. ▪ IT personnel define secure networking practices to protect the Confidentiality, Integrity, Availability and Safety (CIAS) of the organization's TAASD. ▪ Secure Baseline Configurations (SBC) enforce the principles of least privileges and least functionality for boundary protection technologies.
Level 3 — Well Defined
Continuous Monitoring (MON) capabilities are standardized across the entity for applicability to People, Processes, Technologies, Data and/or Facilities (PPTDF) to ensure consistency for Technology Assets, Applications, Services and/or Data (TAASD). Capability criteria associated with this control reasonably expect the following criteria to exist: ▪ Policies and standards associated with MON domain capabilities are formally documented and centrally-managed by the entity's Governance, Risk & Compliance (GRC) team, or similar function. ▪ Cybersecurity personnel use a structured process via Standardized Operating Procedures (SOP) to review and analyze logs. ▪ A Security Operations Center (SOC) team, or similar function, is appropriately staffed and supported to implement and maintain MON domain capabilities. ▪ Technology is leveraged to enhance the efficiency and accuracy of continuous monitoring operations (e.g., Security Incident Event Manager (SIEM)). ▪ The entity's Governance, Risk & Compliance (GRC) team, or similar function, works with business stakeholders and process owners to appropriately scope and reasonably implement cybersecurity and data protection controls associated with MON domain capabilities to address Minimum Compliance Requirements (MCR) (e.g., applicable statutory, regulatory and/or contractual requirements) and Discretionary Security Requirements (DSR) (e.g., entity-required controls). ▪ Secure Baseline Configurations (SBC) enforce security event logging to contain sufficient information to establish necessary details of activity and allow for forensics analysis. ▪ An implemented and operational capability exists to monitor De-Militarized Zone (DMZ) network segments to separate untrusted networks from trusted networks.
Level 4 — Quantitatively Controlled
Network Security (NET) capabilities, in addition to being standardized across the entity and centrally managed to ensure consistency across Technology Assets, Applications, Services and/or Data (TAASD), efforts are metrics driven to provide sufficient insight for decision makers to predict optimal performance, ensure continued operations and/or identify areas for improvement. Capability criteria associated with this control reasonably expect the following criteria to exist: ▪ Applicable SCR-CMM Level 3 (Well Defined) capabilities are implemented and operational. ▪ Metrics reporting includes quantitative analysis of Key Performance Indicators (KPIs). ▪ Metrics reporting includes quantitative analysis of Key Risk Indicators (KRIs). ▪ Scope of metrics, KPIs and KRIs covers organization-wide cybersecurity and data protection controls, including functions performed by third-parties. ▪ Organizational leadership maintains a formal process to objectively review and respond to metrics, KPIs and KRIs (e.g., monthly or quarterly review). ▪ Based on metrics analysis, process improvement recommendations are submitted for review and are handled in accordance with change control processes. ▪ Business and technical stakeholders are involved in reviewing and approving proposed changes to evolve capabilities.
Level 5 — Continuously Improving
Utilize SCR-CMM Level 3 or Level 4 (if available) criteria definitions: ▪ There are no defined Level 5 criteria, since it is reasonable to assume a continuously-improving process is not necessary to operationalize this control. ▪ Level 5 capabilities should be considered “world-class” where the control builds on Level 4 capabilities, but are continuously improving through Artificial Intelligence (AI) and/or Machine Learning (ML) technologies. ▪ While it may be possible to develop responsive capabilities for this control through the use of AI and/or ML technologies, the criteria would be organization-specific to define.
Assessment Objectives
- MON-25_A01 De-Militarized Zone (DMZ) network segments that separate untrusted networks from trusted networks are monitored.
Evidence Requirements
- E-NET-13 Demilitarized Zone (DMZ) & Web Application Firewall (WAF) Configuration
-
Documented evidence of DMZ architecture and Web Application Firewall (WAF) configuration for externally facing services.
Network Security
Technology Recommendations
Micro/Small
- System Security Plan (SSP)
Small
- System Security Plan (SSP)
Medium
- Architectural review board
- System Security Plan (SSP)
Large
- Architectural review board
- System Security Plan (SSP)
Enterprise
- Architectural review board
- System Security Plan (SSP)