Implementing ISO 27001 Annex A 8.30 involves establishing strict governance over outsourced software development to mitigate supply chain risks. This requires enforcing contractual security requirements, automated code scanning (SAST), and mandatory Software Bill of Materials (SBOM) delivery. The primary business benefit is ensuring code integrity and preventing third-party security vulnerabilities from entering production systems.
ISO 27001 Annex A Outsourced Development Implementation Checklist
Use this implementation checklist to achieve compliance with ISO 27001 Annex A 8.30. This control requires that organisations supervise and monitor outsourced software development to ensure that security requirements are met and tested.
1. Define Security Requirements in Contracts
Control Requirement: Security requirements must be legally binding and explicitly defined before development begins.
Required Implementation Step: Update your Master Services Agreement (MSA) to include a specific “Secure Development Schedule”. This must mandate adherence to the OWASP Top 10, prohibit hardcoded credentials, and define specific encryption standards (e.g., AES-256). Do not accept generic “we will use best practices” clauses.
Minimum Requirement: The signed contract specifically lists the security standards the vendor must code against.
2. Mandate a Software Bill of Materials (SBOM)
Control Requirement: You must know the origin of all code and libraries to manage supply chain risk.
Required Implementation Step: Require the outsourced team to deliver a comprehensive SBOM (in CycloneDX or SPDX format) with every release. Use this to scan for known vulnerabilities (CVEs) in the open-source libraries they have imported into your project.
Minimum Requirement: No code is accepted without a list of all third-party dependencies and versions.
3. Implement Enforced Code Scanning (SAST)
Control Requirement: Outsourced code must be free from known technical vulnerabilities.
Required Implementation Step: Configure your repository (e.g., GitHub, GitLab) to reject pull requests from external developers unless they pass an automated Static Application Security Testing (SAST) scan (e.g., SonarQube, Snyk). Block the merge button until High and Critical issues are resolved.
Minimum Requirement: Automated scanners block code commits containing critical vulnerabilities.
4. Segregate Development Environments
Control Requirement: Outsourced developers must not have access to your internal production data or systems.
Required Implementation Step: Provision a dedicated, isolated development environment (VPC or separate subscription) for the vendor. Ensure firewall rules explicitly deny traffic from this environment to your internal corporate network and production databases.
Minimum Requirement: Vendor accounts have zero network route to the Production environment.
5. Anonymise Test Data
Control Requirement: Production PII must never be shared with external developers for testing.
Required Implementation Step: Generate a synthetic dataset or use a data masking tool to scrub all Personally Identifiable Information (PII) before providing a database dump to the outsourced team. Verify that no real customer emails or IDs exist in the file provided.
Minimum Requirement: Developers are given “dummy” data (e.g., John Doe, test@test.com) only.
6. Retain Code Ownership and Repo Control
Control Requirement: You must maintain control over the integrity and availability of the source code.
Required Implementation Step: Host the source code in your organisation’s repository, not the vendor’s. Invite the external developers as “Collaborators” with restricted permissions. If they terminate the contract, you simply revoke their access, retaining all code history.
Minimum Requirement: The code resides in a repo owned by your organisation, not the vendor’s GitHub account.
7. Define Acceptance Testing Criteria
Control Requirement: Code must be verified against security criteria before final acceptance.
Required Implementation Step: Create a “Definition of Done” that includes a successful Dynamic Application Security Test (DAST) or a manual penetration test for major releases. Refuse to sign off on invoices until the security testing report shows a clean bill of health.
Minimum Requirement: Payment milestones are contractually tied to passing security tests.
8. Control Access via Federation or VPN
Control Requirement: Access to development tools must be authenticated and logged.
Required Implementation Step: Do not create permanent internal AD accounts for temporary vendors if possible. Use B2B collaboration features (like Azure AD Guest access) or issue VPN certificates with an automatic expiration date set to the contract end date.
Minimum Requirement: Vendor accounts automatically expire/lock on the project end date.
9. Audit Commit Logs for Hardcoded Secrets
Control Requirement: Credentials must be managed securely and not embedded in the codebase.
Required Implementation Step: Implement a pre-receive hook (e.g., TruffleHog or git-secrets) that scans every commit for patterns matching API keys, private keys, or passwords. Reject the commit immediately if secrets are detected.
Minimum Requirement: Commits containing AWS keys or passwords are technically rejected by the server.
10. Conduct Post-Engagement Revocation
Control Requirement: Access rights must be removed immediately upon completion of the outsourced work.
Required Implementation Step: Create an offboarding checklist specifically for external vendors. On the final day, revoke repository access, disable VPN keys, terminate cloud console access, and rotate any shared API keys they may have used during development.
Minimum Requirement: All vendor access is revoked within 24 hours of contract termination.
ISO 27001 Annex A 8.30 SaaS / GRC Platform Implementation Failure Checklist
| Control Requirement | The ‘Checkbox Compliance’ Trap | The Reality Check |
|---|---|---|
| Contractual Security | SaaS tool stores a PDF named “Contract.pdf”. | The contract is a generic template with no mention of OWASP, encryption, or liability for data breaches. |
| Supply Chain Risk | SaaS tool asks “Is vendor approved?” (Yes/No). | The vendor has imported a Node.js library that hasn’t been updated since 2019 and contains critical RCE vulnerabilities. |
| Code Scanning | SaaS tool checks if you have a “Secure Coding Policy”. | The policy sits in a folder while the outsourced dev hardcodes an admin password into `config.js` for “easy testing”. |
| Data Protection | SaaS tool requires a “Data Transfer Agreement”. | To fix a bug on Friday night, your internal lead emailed a raw CSV of 5,000 customer records to the vendor’s Gmail. |
| Access Control | SaaS tool lists the vendor in the “Third Party” module. | The vendor finished the project 6 months ago, but their SSH keys are still active on your staging server. |
| Repository Control | SaaS tool verifies “Asset Ownership”. | The vendor hosts the code on their private GitLab. If they go bankrupt tomorrow, you lose your entire IP. |
| Secret Management | SaaS tool checks for a “Password Policy”. | The vendor committed the production Stripe API secret key to the repo history, which is now visible to all their other clients. |
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