ISO 27001 Annex A guide

ISO 27001 Annex A 8.25: Secure development life cycle

Embed security activities, ownership and assurance throughout development and acquisition. This independent guide turns that purpose into practical ownership, operating evidence and auditor-ready testing.

Control
8.25
Category
Technological controls
Primary outcome
Embed security ownership, requirements, review and assurance throughout development and acquisition.

What Control 8.25 means in practice

Embed security ownership, requirements, review and assurance throughout development and acquisition. Test the control through the organisation's actual scope, decisions, ownership and operating records rather than relying on a policy reference alone.

For secure development life cycle, proportional design depends on the affected services, information, people and dependencies. The evidence below should be adapted to that real boundary.

Implementation steps

  1. Step 1. Define ownership, scope and operating criteria for secure development life cycle.
  2. Step 2. Implement secure-development lifecycle that fits the organization’s risks, services and working practices.
  3. Step 3. Integrate the activity with relevant change, exception and review processes.
  4. Step 4. Review performance and improve the arrangement when risks, technology or obligations change.

What good implementation looks like

  • security findings fixed and retested before or after risk-approved release
  • sample releases showing required security activities occurred
  • lessons from incidents and defects reflected in standards and tooling

Implementation evidence and effectiveness evidence

Evidence the control is implemented

  • approved secure-development lifecycle
  • design, review and test records
  • assigned ownership and approval evidence
  • sample implementation, review and exception records

Evidence the control is effective

  • security findings fixed and retested before or after risk-approved release
  • sample releases showing required security activities occurred
  • lessons from incidents and defects reflected in standards and tooling

How an auditor may test Control 8.25

  1. Select a representative in-scope service, asset or process.
  2. Confirm the accountable owner and expected operation.
  3. Trace a recent example: Threat modelling identifies trust-boundary risks before implementation.
  4. Inspect the operating record and corroborating technical evidence.
  5. Compare the design with evidence that the control operated effectively.
  6. Follow an exception or adverse result through decision and closure.
  7. Review trends, metrics and improvement decisions.

Questions to prepare for

  • How is secure development life cycle implemented in practice?
  • Who owns the activity and how are decisions approved?
  • Show me a recent example from operation through review.
  • How are exceptions, changes or overdue actions handled?

Practical examples

Example 1

Threat modelling identifies trust-boundary risks before implementation.

Example 2

Code review and automated testing prevent a known authorization weakness from release.

Example 3

A high-risk third-party component has approval, monitoring and upgrade ownership.

Illustrative decision and evidence record

Control outcomeEmbed security ownership, requirements, review and assurance throughout development and acquisition.
Illustrative activityThreat modelling identifies trust-boundary risks before implementation.
Evidence sampleapproved secure-development lifecycle
Effectiveness signalsecurity findings fixed and retested before or after risk-approved release
Auditor questionHow is secure development life cycle implemented in practice?
Failure to challengedocumenting secure development life cycle without consistent operation

Reviewer note: Test secure development life cycle with a recent real example; a current operating record normally reveals more than policy wording alone.

Useful performance and coverage measures

  • critical findings escaping to production
  • security review coverage for high-risk changes
  • overdue development risk exceptions

Approach for smaller and mature organizations

Smaller organization

Use a clear owner, a proportionate working record, built-in platform capability and a scheduled review. Sample real activity instead of creating duplicate paperwork for secure development life cycle.

Mature or complex organization

Define service-level ownership, automated coverage reporting, integrated workflow, risk-based exceptions and independent assurance across business units and technology platforms.

Practical implementation checklist

  • □ Define ownership, scope and operating criteria for secure development life cycle.
  • □ Implement secure-development lifecycle that fits the organization’s risks, services and working practices.
  • □ Integrate the activity with relevant change, exception and review processes.
  • □ Review performance and improve the arrangement when risks, technology or obligations change.
  • □ Sample evidence has been checked for operation and effectiveness.
  • □ Exceptions have owners, rationale, review dates and closure evidence.

Common implementation mistakes

  • documenting secure development life cycle without consistent operation
  • unclear ownership or review frequency
  • evidence that does not cover the full ISMS scope
  • exceptions accepted without risk-based approval or follow-up

Frequently asked questions

Does every change need a full penetration test?

No. Apply assurance proportionate to change and risk using review, automated testing, targeted testing and independent assessment where appropriate.

Is secure coding the same as a secure lifecycle?

Secure coding is one part; the lifecycle also covers requirements, architecture, environments, testing, release and learning.

Can outsourced development use the same process?

Yes, with responsibilities, evidence, acceptance criteria and oversight made explicit in the supplier arrangement.

Use the interactive control lookup

Open Control 8.25 in the free tool to browse connected controls and practical evidence alongside the complete reference set.

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