NET-35: Application Programming Interface (API) Security
Mechanisms exist to ensure support for secure interoperability between components with Application Programming Interfaces (APIs).
Renumbered: Formerly CLD-04 in SCF 2025.4.
Control Question: Does the organization ensure support for secure interoperability between components with Application Programming Interfaces (APIs)?
General (4)
| Framework | Mapping Values |
|---|---|
| CSA CCM 4.1.0 | AIS-08 IPY-02 IPY-03 |
| CSA IoT SCF 2 | CLS-07 CLS-12 CLS-13 |
| ISO 27002 2022 | 5.23 8.26 |
| ISO 27018 2025 | 5.23 8.26 |
US (2)
| Framework | Mapping Values |
|---|---|
| USA Federal DoD Zero Trust Execution Roadmap v1.1 | 6.6 6.6.2 6.6.3 |
| USA Federal 45 CFR 155.260 | 155.260(a)(6) |
EMEA (3)
| Framework | Mapping Values |
|---|---|
| EMEA Germany C5 2026 | PI-01.01B PSS-01.02B.16 |
| EMEA Spain CCN-STIC 825 | mp.info.4 mp.s.2 |
| EMEA Saudi Arabia CSCC-1 2019 | 1-3-2-3 |
APAC (5)
| Framework | Mapping Values |
|---|---|
| APAC India SEBI CSCRF 2024 | PR.AA.S17 |
| APAC Malaysia RMiT 2025 | A5-E1 A5-E1(a) A10-B1(f) A10-B1(f)(i) A10-B1(f)(ii) |
| APAC New Zealand HISF MLHSP 2023 | HHSP52 HML52 |
| APAC New Zealand HISF Suppliers 2023 | HSUP44 |
| APAC Singapore MAS TRM 2021 | 6.4.1 6.4.4 |
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
SCR-CMM Level 1 criteria definitions are not available for this control: ▪ A reasonable person would conclude this control requires a structured process. ▪ At this level of maturity, the "ad hoc" nature of performing a capability informally would indicate the intent of the control is not met due to a lack of consistency and formality.
Level 2 — Planned & Tracked
Cloud Security (CLD) 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 CLD domain capabilities are formally documented and centrally-managed by the entity. ▪ Standardized Operating Procedures (SOP) associated with CLD 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 CLD domain capabilities to address applicable statutory, regulatory and/or contractual requirements for Technology Assets, Applications, Services and/or Data (TAASD). ▪ Cloud management controls-related controls are primarily administrative and preventative in nature (e.g., policies, standards and procedures & guidelines). ▪ Cloud management may be a defined function (e.g., team or department) or assigned as an additional duty to existing IT and/or cybersecurity personnel. ▪ Cloud-based Technology Assets, Applications and/or Services (TAAS) are governed according to the same processes used for on-premises TAAS, where no formal, dedicated cloud governance process exists.
Level 3 — Well Defined
Network Security (NET) 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 NET domain capabilities are formally documented and centrally-managed by the entity's Governance, Risk & Compliance (GRC) team, or similar function. ▪ Standardized Operating Procedures (SOP) associated with NET domain capabilities are well-documented and kept current by process owners. ▪ A network security management team, or similar function, is appropriately staffed and supported to implement and maintain NET domain capabilities. ▪ Technology is leveraged to enhance the efficiency and accuracy of network security operations (e.g., network management solution and log aggregator). ▪ 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 NET 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 the principles of least privileges and least functionality for boundary protection technologies. ▪ An implemented and operational capability exists to ensure support for secure interoperability between components with Application Programming Interfaces (APIs).
Level 4 — Quantitatively Controlled
Utilize SCR-CMM Level 3 criteria definitions: ▪ There are no defined Level 4 criteria, since it is reasonable to assume a quantitatively-controlled process is not necessary to operationalize this control. ▪ While it may be possible to develop “metrics-driven” capabilities for this control, the criteria would be organization-specific to define.
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
- NET-35_A01 information and data exchange between components using Application Programming Interfaces (APIs) supports secure data portability.
- NET-35_A02 secure interoperability between components is supported through the use of Application Programming Interfaces (APIs).
Evidence Requirements
- E-WEB-02 Client-Facing Web Services Protections
-
Documented evidence of protections for client-facing web services, including Strong Customer Authentication (SCA) and secure web traffic.
Website Security
Technology Recommendations
Micro/Small
- Use HTTPS and API keys/OAuth for any APIs; follow OWASP API Security Top 10
Small
- API security standard (authentication, TLS, input validation)
- API inventory
Medium
- API security requirements in SSDP (OAuth 2.0/OIDC, rate limiting, schema validation)
- API inventory and documentation (OpenAPI)
Large
- API security platform (e.g., Salt Security, Noname, 42Crunch)
- API gateway enforcement
- API security testing in CI/CD
Enterprise
- Enterprise API security program (inventory, gateway enforcement, runtime protection, testing)
- API security platform (e.g., Salt, Noname, Akamai API Security)