ISO 27001:2022 Annex A 8.25 – Secure Development Life Cycle Explained

Most software vulnerabilities are not caused by attackers.
They are designed in, long before code ever reaches production.

Annex A 8.25 exists to ensure organisations embed information security throughout the secure development life cycle (SDLC), from initial design through development, testing, deployment, and change.

This control is about building security in, not bolting it on at the end.

ISO 27001

Quick Guide: Annex A 8.25 at a Glance

Annex A 8.25 of ISO 27001:2022 focuses on the secure development of software, systems, and applications.

At a practical level, this means:

  • Integrating security into all stages of development
  • Defining secure development rules and standards
  • Ensuring development, test, and production are separated
  • Applying secure coding and testing practices
  • Controlling source code, changes, and releases
  • Ensuring developers have appropriate security competence

The control does not mandate a specific development methodology. It expects security to be a consistent and explicit part of how systems are built and changed.

In-Depth Guide to Annex A 8.25

What Is Annex A 8.25 and Why Does It Matter?

Historically, many organisations treated security as:

  • A final testing activity
  • A penetration test before go-live
  • A compliance checkbox

The result was predictable:

  • Vulnerabilities discovered late
  • Costly rework
  • Security weaknesses embedded in design
  • Increased operational and incident risk

Annex A 8.25 ensures organisations address security from the outset, when change is cheapest and risk is easiest to control.

This control replaces ISO 27001:2013 Annex A 14.2.1 and strengthens expectations around testing, licensing, and secure engineering practices.

How to Implement Annex A 8.25 Effectively

A pragmatic approach to Annex A 8.25 typically includes the following elements.

1. Define a Secure Development Policy or Framework

Organisations should define rules covering:

  • Secure development principles
  • Approved development practices
  • Responsibilities across the SDLC

This applies to:

  • In-house development
  • Customisation
  • Low-code and configuration-based development
  • Outsourced or third-party development

Security should be part of “how we develop”, not an optional overlay.

2. Integrate Security Into Planning and Design

Security requirements should be considered during:

  • Requirements gathering
  • Architecture and design
  • Technology selection

This may include:

  • Threat modelling
  • Security requirements definition
  • Design reviews

Fixing a design flaw later is significantly more expensive.

3. Separate Development, Test, and Production Environments

Annex A 8.25 explicitly supports environment separation.

Organisations should ensure:

  • Development, test, and production are segregated
  • Production data is protected from misuse
  • Changes cannot bypass testing and approval

Environment separation reduces both security and operational risk.

4. Apply Secure Coding Practices

Where code is written, organisations should:

  • Define secure coding standards per language or platform
  • Address common vulnerability classes
  • Avoid unsafe functions and patterns

Secure coding expectations should be:

  • Documented
  • Enforced
  • Reviewed

Insecure code is rarely accidental — it is usually unmanaged.

5. Control Use of Libraries, Components, and Licences

Modern development relies heavily on third-party components.

Annex A 8.25 expects organisations to:

  • Control use of open-source and third-party libraries
  • Understand licensing obligations
  • Assess security and support risks
  • Identify safer or cost-effective alternatives

Supply chain risk does not stop at infrastructure.

6. Perform Security Testing Throughout Development

Security testing should not be limited to the end of development.

Organisations should consider:

  • Code scanning
  • Dependency analysis
  • Vulnerability scanning
  • Security testing during development and testing phases

Annex A 8.25 explicitly supports:

  • Security and system testing
  • Penetration testing where risk justifies it

Late testing finds problems when options are limited.

7. Protect Source Code and Development Artefacts

Source code and configurations should be:

  • Stored in secure repositories
  • Access-controlled
  • Version-controlled
  • Protected against unauthorised change

This aligns closely with:

Uncontrolled code repositories are high-value targets.

8. Apply Change Control to Development Outputs

Changes introduced through development should:

  • Follow formal change management
  • Be reviewed and approved
  • Be traceable from requirement to release

This supports:

  • Accountability
  • Auditability
  • Safer deployment

Rapid delivery does not remove the need for control.

9. Ensure Developers Have Appropriate Security Competence

Annex A 8.25 explicitly recognises people as a control.

Organisations should ensure developers:

  • Understand secure development principles
  • Can recognise common security flaws
  • Receive appropriate application security training

Tools do not compensate for lack of knowledge.

10. Control Outsourced and Third-Party Development

Where development is outsourced, organisations should ensure:

  • Secure development requirements are defined contractually
  • External developers follow internal standards
  • Security testing and review still occur

Outsourced development remains organisational risk.

In-Depth Guide to Annex A 5.1

What is Annex A 5.1 and Why Does It Matter?

  • What the organisation values
  • How security decisions are approached
  • Where accountability sits
  • Aligns security with business objectives
  • Supports proportionate, risk-based decisions
  • Provides a reference point during incidents and disputes
  • Creates consistency without bureaucracy

How to Implement Annex A 5.1 Effectively

1. Define a Comprehensive Information Security Policy
  • Scope: What the policy applies to (systems, data, people).
  • Objectives: Why security is important for the business.
  • Roles & Responsibilities: Who is accountable for security.
  • Key Principles: Risk management, access control, and data protection.
2. Secure Senior Management Approval
  • Review and approve policies.
  • Ensure resources are allocated for implementation.
  • Lead by example in enforcing security policies.
3. Communicate and Train Employees
  • Include security policies in onboarding and ongoing training.
  • Ensure policies are easily accessible to all employees.
  • Encourage acknowledgment and acceptance of security responsibilities.
4. Regular Review & Continuous Improvement
  • Set a schedule for periodic policy reviews (at least annually).
  • Update policies based on business changes, new threats, or regulatory updates.
  • Conduct audits to ensure compliance and effectiveness.
5. Integrate Policies into the ISMS
  • Use it to develop more detailed security procedures.
  • Ensure policies align with other Annex A controls and broader risk management practices.
Key Differences: ISO 27001:2013 vs ISO 27001:2022
AspectISO 27001:2013ISO 27001:2022
Control StructureTwo separate controls: 5.1.1 & 5.1.2Merged into one control (5.1)
Implementation GuidanceLess prescriptiveMore detailed guidance for policy creation and alignment
Awareness & TrainingNot explicitly mentionedExplicitly requires policies to be part of training programmes
Attributes TableNot includedew attributes table for mapping policies to industry terms
Common Challenges & How to Overcome Them
  • Challenge: Employees don’t follow security policies.
  • Solution: Make policies practical and relevant to daily work. Use real-world examples in training.
  • Challenge: Policies are outdated or too generic.
  • Solution: Schedule annual reviews and update policies based on real threats and business changes.
  • Challenge: Policies are written in technical jargon.
  • Solution: Use plain language that all employees can understand.
  • Challenge: Lack of leadership buy-in.
  • Solution: Show how weak security affects business objectives—costs of breaches, loss of client trust, and legal penalties.
Final Recommendations
  • Make security policies living documents—review, refine, and update regularly.
  • Use policy training and awareness to create a security-conscious workforce.
  • Ensure policies are accessible, relevant, and easy to understand.
  • Keep policies aligned with business strategy and regulatory requirements.
  • Engage leadership in driving security culture from the top down.

Practical Considerations

Annex A 8.25 does not require:

  • A specific SDLC model
  • Heavy-weight bureaucracy
  • Slowing delivery unnecessarily

It does require organisations to:

  • Embed security into development activity
  • Prevent predictable design and coding failures
  • Be able to demonstrate security was considered

Most serious application vulnerabilities are known patterns repeated.

Common Challenges and How to Overcome Them

  • Security only tested at the end
  • Integrate security throughout the SDLC
  • Developers unaware of security expectations
  • Define standards and provide training
  • Uncontrolled use of third-party libraries
  • Govern components and licensing
  • Production changes bypass testing
  • Enforce environment separation and change control

Secure development failures are usually process failures.

In-Depth Guide to Annex A 5.1

What is Annex A 5.1 and Why Does It Matter?

  • What the organisation values
  • How security decisions are approached
  • Where accountability sits
  • Aligns security with business objectives
  • Supports proportionate, risk-based decisions
  • Provides a reference point during incidents and disputes
  • Creates consistency without bureaucracy

How to Implement Annex A 5.1 Effectively

1. Define a Comprehensive Information Security Policy
  • Scope: What the policy applies to (systems, data, people).
  • Objectives: Why security is important for the business.
  • Roles & Responsibilities: Who is accountable for security.
  • Key Principles: Risk management, access control, and data protection.
2. Secure Senior Management Approval
  • Review and approve policies.
  • Ensure resources are allocated for implementation.
  • Lead by example in enforcing security policies.
3. Communicate and Train Employees
  • Include security policies in onboarding and ongoing training.
  • Ensure policies are easily accessible to all employees.
  • Encourage acknowledgment and acceptance of security responsibilities.
4. Regular Review & Continuous Improvement
  • Set a schedule for periodic policy reviews (at least annually).
  • Update policies based on business changes, new threats, or regulatory updates.
  • Conduct audits to ensure compliance and effectiveness.
5. Integrate Policies into the ISMS
  • Use it to develop more detailed security procedures.
  • Ensure policies align with other Annex A controls and broader risk management practices.
Key Differences: ISO 27001:2013 vs ISO 27001:2022
AspectISO 27001:2013ISO 27001:2022
Control StructureTwo separate controls: 5.1.1 & 5.1.2Merged into one control (5.1)
Implementation GuidanceLess prescriptiveMore detailed guidance for policy creation and alignment
Awareness & TrainingNot explicitly mentionedExplicitly requires policies to be part of training programmes
Attributes TableNot includedew attributes table for mapping policies to industry terms
Common Challenges & How to Overcome Them
  • Challenge: Employees don’t follow security policies.
  • Solution: Make policies practical and relevant to daily work. Use real-world examples in training.
  • Challenge: Policies are outdated or too generic.
  • Solution: Schedule annual reviews and update policies based on real threats and business changes.
  • Challenge: Policies are written in technical jargon.
  • Solution: Use plain language that all employees can understand.
  • Challenge: Lack of leadership buy-in.
  • Solution: Show how weak security affects business objectives—costs of breaches, loss of client trust, and legal penalties.
Final Recommendations
  • Make security policies living documents—review, refine, and update regularly.
  • Use policy training and awareness to create a security-conscious workforce.
  • Ensure policies are accessible, relevant, and easy to understand.
  • Keep policies aligned with business strategy and regulatory requirements.
  • Engage leadership in driving security culture from the top down.

Final Recommendations

Annex A 8.25 is about reducing risk before systems ever go live.

When a secure development life cycle is implemented effectively:

  • Fewer vulnerabilities reach production
  • Security testing becomes cheaper and faster
  • Operational risk is reduced
  • Confidence in systems increases

You cannot patch your way out of poor design.
Annex A 8.25 ensures organisations design security in from the start.

In-Depth Guide to Annex A 5.1

What is Annex A 5.1 and Why Does It Matter?

  • What the organisation values
  • How security decisions are approached
  • Where accountability sits
  • Aligns security with business objectives
  • Supports proportionate, risk-based decisions
  • Provides a reference point during incidents and disputes
  • Creates consistency without bureaucracy

How to Implement Annex A 5.1 Effectively

1. Define a Comprehensive Information Security Policy
  • Scope: What the policy applies to (systems, data, people).
  • Objectives: Why security is important for the business.
  • Roles & Responsibilities: Who is accountable for security.
  • Key Principles: Risk management, access control, and data protection.
2. Secure Senior Management Approval
  • Review and approve policies.
  • Ensure resources are allocated for implementation.
  • Lead by example in enforcing security policies.
3. Communicate and Train Employees
  • Include security policies in onboarding and ongoing training.
  • Ensure policies are easily accessible to all employees.
  • Encourage acknowledgment and acceptance of security responsibilities.
4. Regular Review & Continuous Improvement
  • Set a schedule for periodic policy reviews (at least annually).
  • Update policies based on business changes, new threats, or regulatory updates.
  • Conduct audits to ensure compliance and effectiveness.
5. Integrate Policies into the ISMS
  • Use it to develop more detailed security procedures.
  • Ensure policies align with other Annex A controls and broader risk management practices.
Key Differences: ISO 27001:2013 vs ISO 27001:2022
AspectISO 27001:2013ISO 27001:2022
Control StructureTwo separate controls: 5.1.1 & 5.1.2Merged into one control (5.1)
Implementation GuidanceLess prescriptiveMore detailed guidance for policy creation and alignment
Awareness & TrainingNot explicitly mentionedExplicitly requires policies to be part of training programmes
Attributes TableNot includedew attributes table for mapping policies to industry terms
Common Challenges & How to Overcome Them
  • Challenge: Employees don’t follow security policies.
  • Solution: Make policies practical and relevant to daily work. Use real-world examples in training.
  • Challenge: Policies are outdated or too generic.
  • Solution: Schedule annual reviews and update policies based on real threats and business changes.
  • Challenge: Policies are written in technical jargon.
  • Solution: Use plain language that all employees can understand.
  • Challenge: Lack of leadership buy-in.
  • Solution: Show how weak security affects business objectives—costs of breaches, loss of client trust, and legal penalties.
Final Recommendations
  • Make security policies living documents—review, refine, and update regularly.
  • Use policy training and awareness to create a security-conscious workforce.
  • Ensure policies are accessible, relevant, and easy to understand.
  • Keep policies aligned with business strategy and regulatory requirements.
  • Engage leadership in driving security culture from the top down.

The Annex Control Table

ISO 27001:2022 Organisational Controls
ISO 27001:2022 Technological Controls