TDA-16.1: Access to Program Source Code
Mechanisms exist to limit privileges to change software resident within software libraries.
Renumbered: Formerly TDA-20 in SCF 2025.4.
Control Question: Does the organization limit privileges to change software resident within software libraries?
General (14)
| Framework | Mapping Values |
|---|---|
| GovRAMP | SA-04(02) |
| GovRAMP High | SA-04(02) |
| ISO 27002 2022 | 8.4 8.30 |
| ISO 27017 2015 | 9.4.5 14.2.4 |
| ISO 27018 2025 | 8.4 8.30 |
| MPA Content Security Program 5.3.1 | TS-1.15 |
| NIST 800-53 R5.2 | SA-04(02) |
| NIST 800-53B R5 (moderate) (source) | SA-04(02) |
| NIST 800-53B R5 (high) (source) | SA-04(02) |
| NIST 800-82 R3 | SA-04(02) |
| NIST 800-82 R3 MODERATE OT Overlay | SA-04(02) |
| NIST 800-82 R3 HIGH OT Overlay | SA-04(02) |
| NIST 800-218 | PS.1.1 |
| UL 2900-1 2017 | 4.1(d) |
US (10)
| Framework | Mapping Values |
|---|---|
| USA Federal CMS MARS-E 2.0 | SA-4(2) |
| USA Federal DHS CISA SSDAF | 2 3 |
| USA Federal DoD Zero Trust Execution Roadmap v1.1 | 3.3.1 |
| USA Federal EO 14028 | 4e(iii) 4e(vi) |
| USA Federal CJIS Security Policy 6.0 | SA-4(2) |
| USA Federal FedRAMP R5 (moderate) | SA-04(02) |
| USA Federal FedRAMP R5 (high) | SA-04(02) |
| USA Federal IRS 1075 2021 | SA-4(CE-2) |
| USA California CCPA 2025 | 7123(c)(14) |
| USA Texas TX-RAMP Level 2 | SA-04 (02) |
EMEA (5)
| Framework | Mapping Values |
|---|---|
| EMEA Germany BAIT 2017 | 7.9 |
| EMEA EU DORA RTS 2024 | Article 16.2(e) |
| EMEA EU EBA GL/2019/04 | 3.6.2.73 |
| EMEA LUX CCSF 20/750 2020 | 3.6.2-73 |
| EMEA Saudi Arabia CSCC-1 2019 | 1-3-2-2 |
APAC (5)
| Framework | Mapping Values |
|---|---|
| APAC Australia ISM June 2026 | ISM-1422 |
| APAC Japan ISMAP | 9.4.5 9.4.5.1 9.4.5.2 9.4.5.3 9.4.5.4 9.4.5.5 9.4.5.6 9.4.5.7 9.4.5.8 9.4.5.9 14.2.1.5 |
| APAC New Zealand HISF MLHSP 2023 | HHSP42 HML42 |
| APAC New Zealand HISF Suppliers 2023 | HSUP37 |
| APAC Singapore MAS TRM 2021 | 7.6.2 |
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
Technology Development & Acquisition (TDA) 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 TDA domain capabilities are formally documented and centrally-managed by the entity. ▪ Standardized Operating Procedures (SOP) associated with TDA 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 TDA domain capabilities to address applicable statutory, regulatory and/or contractual requirements for Technology Assets, Applications, Services and/or Data (TAASD). ▪ Technology development and acquisition-related controls are primarily administrative and preventative in nature (e.g., policies, standards and procedures & guidelines). ▪ Technology development and acquisition management may be a defined function (e.g., team or department) or assigned as an additional duty to existing IT and/or cybersecurity personnel. ▪ Secure development practices mostly conform to industry-recognized standards for secure engineering of Technology Assets, Applications and/or Services (TAAS) (e.g., OWASP, NIST SP 800-218 and NIST SP 800-160). ▪ An application development team, or similar function, uses a structured process to design, build and maintain secure configurations for test, development, staging and production environments. ▪ An application development team, or similar function, uses a Source Code Manager (SCM) solution to govern modifying, copying, deleting, moving and renaming items in the software library. ▪ SCM supports integrity checking on the source code repository. ▪ SCM uses Role-Based Access Controls (RBAC) to limit the logical access and permissions for users in the software library.
Level 3 — Well Defined
Technology Development & Acquisition (TDA) 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 TDA 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 TDA domain capabilities are well-documented and kept current by process owners. ▪ A software development team, or similar function, is appropriately staffed and supported to implement and maintain TDA domain capabilities. ▪ Technology is leveraged to enhance the efficiency and accuracy of technology development and acquisition management (e.g., project management software, software escrow solution and software testing tools). ▪ 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 TDA 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). ▪ An implemented and operational capability exists to limit privileges to change software resident within software libraries.
Level 4 — Quantitatively Controlled
Technology Development & Acquisition (TDA) 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
- TDA-16.1_A01 organization-defined criteria for security-relevant information pertaining to external system interfaces, high-level design, low-level design, source code or hardware schematics and design and implementation information are documented in a System Security Plan (SSP).
- TDA-16.1_A02 the developer of the system, system component or system service is required to provide design and implementation information for the controls that includes using at level of detail.
Evidence Requirements
- E-TDA-20 Development / Test / Production Environment Separation
-
Documented evidence of secure development environments and separation of development, test and production environments, including secure migration practices.
Technology Design & Acquisition
Technology Recommendations
Micro/Small
- Source code in private repository with access limited to developers
Small
- Source control with role-based access (e.g., GitHub, GitLab, Azure DevOps)
- Branch protection
Medium
- Source code access control with least privilege
- Protected branches and required reviews
- Access reviews
Large
- Enterprise SCM with RBAC, protected branches, signed commits
- Periodic access recertification
- Audit logging
Enterprise
- Enterprise source code governance (RBAC, protected branches, signed commits, access recertification)
- Integration with identity governance
- Code repository monitoring