Industry Standards for Software Supply Chain Security¶

REFERENCE GUIDE This comprehensive guide examines key industry standards and frameworks that specifically address or can be applied to software supply chain security. Understanding and implementing these standards is crucial for establishing robust software supply chain security controls.

Standards Landscape¶

The software supply chain security standards landscape continues to evolve in response to increasing threats. These standards provide organizations with structured approaches to secure their software development lifecycle and supply chain.

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    A[Standards for Software Supply Chain Security]:::general --> B[General Security<br/>Standards]:::general
    A --> C[Supply Chain<br/>Specific Standards]:::specific
    A --> D[Cryptographic<br/>Standards]:::crypto
    A --> E[Privacy & Data<br/>Protection]:::privacy
    A --> F[Best Practices &<br/>Guidance]:::guidance

    B --> B1[ISO/IEC 27001<br/>ISMS]:::general
    B --> B2[NIST CSF]:::general
    B --> B3[SOC 2]:::general

    C --> C1[SLSA]:::specific
    C --> C2[NIST SP 800-161<br/>Supply Chain Risk]:::specific
    C --> C3[ISO/IEC 27036<br/>Supplier Relationships]:::specific

    D --> D1[FIPS 140-2/3<br/>Cryptographic Modules]:::crypto
    D --> D2[ISO/IEC 19790<br/>Security Requirements]:::crypto

    E --> E1[GDPR]:::privacy
    E --> E2[CCPA/CPRA]:::privacy

    F --> F1[OWASP Top 10]:::guidance
    F --> F2[CIS Controls]:::guidance
    F --> F3[SANS Top 25]:::guidance

    click C1 "#slsa" "Supply chain Levels for Software Artifacts"
    click C2 "#nist-sp-800-161" "NIST Supply Chain Risk Management"
    click B1 "#isoiec-27001" "Information Security Management Systems"

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General Security Standards¶

ISO/IEC 27001¶

ISO/IEC 27001 is an international standard for information security management systems (ISMS). While not specifically designed for software supply chain security, it provides a comprehensive framework that can be applied to secure the various components of software supply chains.

Key Aspects for Supply Chain Security:¶

Annex A.14: System acquisition, development and maintenance
Annex A.15: Supplier relationships
Annex A.8: Asset management (tracking dependencies)

Implementation Approach:¶

Conduct a risk assessment of your software supply chain
Develop security controls based on identified risks
Implement a continuous monitoring and improvement process
Seek certification through an accredited body

Implementation Guidance

Begin with scope definition centered on supply chain elements
Develop specific controls for third-party code assessment
Establish explicit supplier security requirements
Create documentation for the verification of external components
Implement monitoring solutions for supply chain indicators

NIST Cybersecurity Framework¶

The NIST Cybersecurity Framework (CSF) provides a policy framework for private sector organizations to assess and improve their ability to prevent, detect, and respond to cyber attacks. The framework is structured around five core functions:

Identify: Develop an organizational understanding of risks to systems, assets, data, and capabilities
Protect: Implement safeguards to ensure delivery of critical infrastructure services
Detect: Implement activities to identify cybersecurity events
Respond: Implement activities to take action regarding detected cybersecurity events
Recover: Implement activities to maintain resilience and restore capabilities impaired by cybersecurity events

Application to Supply Chain Security:¶

The NIST CSF can be mapped to software supply chain security as follows:

Identify: Inventory all software dependencies, build processes, and deployment pipelines
Protect: Implement secure coding practices, dependency scanning, and artifact signing
Detect: Deploy monitoring for unauthorized changes, suspicious build patterns, or compromised dependencies
Respond: Establish protocols for addressing identified supply chain compromises
Recover: Create backup systems and restoration procedures for clean rebuilds

CSF Implementation Tiers

Organizations can assess their maturity in supply chain security using the CSF tiers:

Tier 1 (Partial): Ad-hoc processes, limited awareness
Tier 2 (Risk Informed): Risk management but not organization-wide
Tier 3 (Repeatable): Formal policies, integrated throughout the organization
Tier 4 (Adaptive): Continuous improvement, proactive security posture

Supply Chain Specific Standards¶

NIST SP 800-161¶

SUPPLY CHAIN SPECIFIC NIST Special Publication 800-161, "Supply Chain Risk Management Practices for Federal Information Systems and Organizations," provides guidance specifically for managing supply chain risks in information systems.

Key Components:¶

Multi-tiered risk management approach addressing organization, mission, and system levels
Supply chain risk assessment process tailored for software components
Controls implementation guidance for different phases of the system development lifecycle
Countermeasures specifically for software supply chain risks

Implementation in Software Development:¶

Implementation Examples:
  - Establish a Software Component & Supplier Inventory Database
  - Create Code Provenance Verification Procedures
  - Implement Build Environment Security Requirements
  - Develop Dependency Update Policies and Procedures
  - Design Incident Response Plans for Supply Chain Compromises

Supply chain Levels for Software Artifacts (SLSA)¶

EMERGING STANDARD SLSA (pronounced "salsa") is a security framework, a check-list of standards and controls to prevent tampering, improve integrity, and secure packages and infrastructure in your projects, businesses or enterprises.

SLSA is designed specifically to address software supply chain security with four progressive levels of maturity:

SLSA Level	Description	Requirements
Level 1	Build process documentation	- Documentation of the build process - Provenance available
Level 2	Tamper resistance	- Hosted build service with minimal security controls - Requires source version control - Generated provenance
Level 3	Build service security	- Security controls on build service - Build as code (parameterized) - Ephemeral environment with isolated builds
Level 4	Highest security assurance	- Two-party review of build configuration changes - Hermetic builds (fully defined dependencies) - Reproducible builds when possible

Implementation Example:¶

# Example of generating SLSA provenance for a container image
slsa-provenance generate \
  --artifact-path my-container:latest \
  --builder-id "https://github.com/slsa-framework/slsa-github-generator/.github/workflows/generator_container_slsa3.yml@main" \
  --output provenance.json

ISO/IEC 27036¶

ISO/IEC 27036 is a multi-part standard focused specifically on information security for supplier relationships. Part 4 specifically addresses security guidelines for securing the software supply chain, including:

Software acquisition process security
Security requirements specification
Acceptance testing and review
Software deployment security
Monitoring and maintenance of acquired software

Application Security Standards¶

OWASP Top Ten¶

The OWASP Top Ten identifies the most critical web application security risks. While focusing broadly on application security, several categories directly address supply chain concerns:

OWASP Category	Supply Chain Security Relevance
A06:2021 - Vulnerable and Outdated Components	Directly addresses dependency management, a core supply chain concern
A08:2021 - Software and Data Integrity Failures	Covers CI/CD pipeline security, code signing, and update verification
A09:2021 - Security Logging and Monitoring Failures	Critical for detecting potential supply chain compromises

Implementation Tips

Run automated tools to scan for vulnerable dependencies
Implement artifact signing to ensure integrity
Establish monitoring for unusual build patterns
Maintain an inventory of all third-party components
Set up alerting for any unauthorized changes to build scripts

CIS Controls¶

The Center for Internet Security (CIS) Controls are a set of best practices designed to help organizations improve their cybersecurity posture. Several CIS Controls directly apply to securing the software supply chain:

Control 2: Inventory and Control of Software Assets
Control 4: Secure Configuration of Enterprise Assets and Software
Control 7: Continuous Vulnerability Management
Control 14: Security Awareness and Skills Training
Control 18: Application Software Security

Implementation Example for Control 7:¶

Continuous Vulnerability Management:
  - Implement automated dependency scanning in CI/CD pipelines
  - Establish regular dependency update cadence
  - Document and test remediation processes for vulnerable components
  - Create risk assessment process for evaluating new dependencies
  - Deploy runtime monitoring for known vulnerabilities

SANS Top 25¶

The SANS Institute's Top 25 Most Dangerous Software Errors highlights the most critical programming errors that can lead to security vulnerabilities. Key areas related to supply chain security include:

Improper Input Validation (particularly when consuming third-party data sources)
Path Traversal (relevant for build systems and dependency resolution)
Cross-Site Request Forgery (impacting package management systems)
Unrestricted Upload of File with Dangerous Type (affecting artifact repositories)

Compliance and Regulatory Standards¶

PCI DSS¶

The Payment Card Industry Data Security Standard (PCI DSS) ensures that all companies that accept, process, store, or transmit credit card information maintain a secure environment. Supply chain relevant requirements include:

Requirement 6: Develop and maintain secure systems and applications
Requirement 11: Regularly test security systems and processes
Requirement 12: Maintain an information security policy

The General Data Protection Regulation (GDPR) addresses data protection and privacy. Key supply chain concerns include:

Processor requirements: Ensuring third-party components maintain data protection
Data protection by design: Including security in supplier selection
Breach notification: Supply chain compromises affecting personal data

Audit and Assurance Standards¶

SSAE 18 / SOC 2¶

The Statement on Standards for Attestation Engagements (SSAE) 18 and the resulting SOC 2 reports provide assurance about controls related to security, availability, processing integrity, confidentiality, and privacy.

Supply Chain Security Considerations:¶

Vendor Management: Assessing security postures of software suppliers
Change Management: Ensuring secure software update processes
Risk Management: Identifying and mitigating third-party software risks
Access Controls: Limiting access to build systems and code repositories

Trust Services Criteria for Supply Chain:¶

Security: Protection against unauthorized access to build systems
Availability: Ensuring the reliability of dependency sources
Processing Integrity: Ensuring build processes operate as expected
Confidentiality: Protecting sensitive information in the supply chain

SOC 2 Assessment Areas for Supply Chain

Code repository access controls
Build server security measures
Dependency management processes
Artifact repository security
Development environment isolation
Third-party code review procedures

FIPS 140-⅔¶

The Federal Information Processing Standard (FIPS) 140-⅔ specifies security requirements for cryptographic modules. Key aspects for software supply chains include:

Module authentication: Ensuring the authenticity of software components
Key management: Properly handling signing keys for code and artifacts
Self-tests: Verifying the integrity of cryptographic operations
Secure design: Implementing secure cryptographic operations in software

Implementing Standards in Your Organization¶

To effectively implement these standards in your organization:

Perform Gap Analysis: Compare your current practices against the most relevant standards
Prioritize by Risk: Address the highest-risk areas of your supply chain first
Create an Implementation Roadmap: Plan phased implementation based on resource availability
Document Compliance: Maintain evidence of adherence to chosen standards
Conduct Regular Audits: Periodically verify continued compliance

IMPORTANT Standards should be implemented based on your organization's risk profile, resources, and specific requirements. Not all standards will be applicable to every organization, and implementation should be tailored accordingly.

Standards Comparison Matrix¶

Standard	Primary Focus	Supply Chain Applicability	Implementation Complexity	Best For
ISO/IEC 27001	Overall Information Security	Medium	High	Organizations seeking comprehensive security framework
NIST CSF	Cybersecurity Risk Management	Medium-High	Medium	Flexible implementation based on risk profile
SLSA	Software Supply Chain Security	Very High	Varies by level	Progressive implementation of supply chain controls
NIST SP 800-161	Supply Chain Risk Management	Very High	High	Organizations with complex supply chains
OWASP Top 10	Application Security	Medium	Low	Starting point for securing applications
CIS Controls	Practical Security Actions	Medium	Medium	Prioritized, practical security implementations
FIPS 140-2/3	Cryptographic Module Security	Low-Medium	High	Government systems and regulated industries

Conclusion¶

Adopting relevant security standards is a critical component of securing your software supply chain. By understanding and implementing these standards, organizations can systematically identify and address security risks throughout their development lifecycle and supply chain.

Remember that standards implementation should be viewed as an ongoing process rather than a one-time event, with regular reviews and updates to address emerging threats and changing requirements.