If you were building a bank vault, you wouldn’t build the walls first and then try to figure out where to drill the holes for the locks. You would design the security into the blueprints from day one. This is exactly what ISO 27001:2022 Annex A 8.25 is about.
Annex A 8.25, titled “Secure development life cycle,” is designed to move your organisation away from “bolt-on” security—where you fix bugs after a breach—toward “built-in” security. It mandates that security rules be established and applied throughout the entire software development life cycle (SDLC).
Table of contents
What is the Objective of Annex A 8.25?
The objective is to ensure that information security is designed and implemented within the development process of software and systems. Whether you are building a massive enterprise platform, a small internal tool, or just an API integration, you need a defined process that ensures security is considered at every stage: from the initial idea to the final deployment.
Step-by-Step Implementation Guide
Implementing a Secure SDLC (SSDLC) doesn’t mean you have to slow down your development team with endless paperwork. It means creating “guardrails” that keep the code secure whilst it moves fast. Here is a practical approach.
1. Establish Your Secure Development Policy
Before writing code, you need to write the rules. You must establish a policy that defines how your organisation develops software securely. This policy should mandate that security is not optional.
According to the experts at Hightable.io, this policy should cover the entire lifecycle. It needs to specify:
- Security Requirements: How you identify security needs during the planning phase.
- Secure Coding Standards: Which standards developers must follow (e.g., OWASP Top 10).
- Checkpoints: The “gates” a project must pass through to move to the next stage.
- Repo Security: How access to code repositories is managed (e.g., enforcing Multi-Factor Authentication).
2. Integrate Security into Requirements and Design
Security starts before the first line of code is written. When you are gathering requirements for a new feature, you must also gather security requirements. For example, if the feature involves user logins, the security requirement might be “passwords must be hashed using bcrypt.”
During the design phase, you should perform threat modelling. Ask the question: “How would a hacker attack this design?” This allows you to architect defenses (like encryption or segmentation) into the foundation of the software.
3. Secure the Development Environment
You cannot build a secure car in an insecure factory. You must ensure that the environment where code is written and tested is secure. This involves strictly separating your development, testing, and production environments (which also helps you comply with Annex A 8.31).
Developers should not have write access to production, and test environments should not contain live production data unless it has been anonymised.
4. Implement Security Gates (Checkpoints)
This is the most critical part of the implementation. You need formal “checkpoints” where security is verified. If the code fails a check, it doesn’t go forward. Common checkpoints include:
- Peer Code Review: Another developer reviews the code for logic errors and security flaws.
- Static Analysis (SAST): Automated tools scan the code for vulnerabilities as it is committed.
- Dynamic Analysis (DAST): Automated tools scan the running application for weaknesses.
- Manual Penetration Testing: For high-risk releases, a human expert tries to break the system.
5. Competence and Training
Your developers are your first line of defence. Annex A 8.25 requires that they are competent in secure coding. You should provide regular training on current threats and secure coding techniques. If a developer doesn’t know what SQL Injection is, they cannot write code to prevent it.
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Common Pitfalls to Avoid
Treating it as a “One-Off”: Secure development is a cycle, not a straight line. Security doesn’t end when the software is deployed; you must have processes for patching and updating it securely.
Ignoring Outsourced Development: If you hire an external agency, you are still responsible. You must ensure their SDLC meets your standards. As Hightable.io suggests, you should demand evidence of their secure development practices—don’t just take their word for it.
A Quick Checklist for Annex A 8.25
To ensure you are ready for your audit, can you answer “Yes” to these questions?
- Do you have a documented Secure Development Policy?
- Are security requirements defined for every new project?
- Do you use version control (like Git) with strict access controls?
- Are development, test, and production environments separated?
- Is code scanned or reviewed for vulnerabilities before deployment?
- Do developers receive training on secure coding?
Why This Matters
Implementing Annex A 8.25 is one of the most effective ways to reduce your cyber risk. Fixing a security bug during the design phase costs pennies; fixing it in production can cost millions in data breach fines and reputation damage. By baking security into your process, you protect your customers and your bottom line.
About the author
Stuart Barker is a veteran practitioner with over 30 years of experience in systems security and risk management.
Holding an MSc in Software and Systems Security, Stuart combines academic rigor with extensive operational experience. His background includes over a decade leading Data Governance for General Electric (GE) across Europe, as well as founding and exiting a successful cyber security consultancy.
As a qualified ISO 27001 Lead Auditor and Lead Implementer, Stuart possesses distinct insight into the specific evidence standards required by certification bodies. He has successfully guided hundreds of organizations – from high-growth technology startups to enterprise financial institutions – through the audit lifecycle.
His toolkits represents the distillation of that field experience into a standardised framework. They move beyond theoretical compliance, providing a pragmatic, auditor-verified methodology designed to satisfy ISO/IEC 27001:2022 while minimising operational friction.
