Manual Code Review Requirements

PCI DSS 4.0.1 Requirement 6.2.3.1 expects that, if you rely on manual code reviews for bespoke/custom software before production release, the review is performed by someone other than the author who is trained in secure code review, and management approves the change before release (PCI DSS v4.0.1 Requirement 6.2.3.1). To operationalize it, you need an enforced workflow in your SDLC and change process plus auditable evidence from your code repo and ticketing system.

Key takeaways:

• Independent review means “not the author,” and the reviewer must be demonstrably competent in secure code review.
• “Management approval” must be explicit, recorded, and tied to the release decision before production deployment.
• Your fastest path to audit-ready is repo-enforced pull request rules plus change tickets that show approvals and traceability.

Manual code review requirements fail in practice for one reason: teams do the reviews, but can’t prove independence, reviewer competency, and management approval at release time. PCI DSS 4.0.1 Requirement 6.2.3.1 is narrow and operator-focused. It does not mandate that you must perform manual code reviews for every change; it sets conditions you must meet if manual reviews are part of your pre-production assurance approach for bespoke and custom software (PCI DSS v4.0.1 Requirement 6.2.3.1).

For a CCO, Compliance Officer, or GRC lead, the operational goal is simple: make the engineering workflow produce evidence by default. You want a repeatable path from “code change” → “independent secure review” → “management approval” → “production release,” with the approvals captured in systems of record (source control, CI/CD, and change management). This page gives you requirement-level implementation guidance you can hand to Engineering and Internal Audit, including the minimum artifacts to retain, the most common audit hangups, and a pragmatic execution plan.

Regulatory text

PCI DSS 4.0.1 Requirement 6.2.3.1 (excerpt): “If manual code reviews are performed for bespoke and custom software prior to release to production, code changes are reviewed by individuals other than the originating code author and who are knowledgeable about code-review techniques and secure coding practices, and code changes are reviewed and approved by management prior to release.” (PCI DSS v4.0.1 Requirement 6.2.3.1)

Operator interpretation (what the assessor will look for):

• You use manual code review as a control for bespoke/custom software changes before production.
• Reviews are independent (reviewer ≠ author).
• Reviewers are qualified (secure coding + code review technique competence is provable).
• Management approval occurs before production release and is recorded.

If you say you perform manual reviews, you must be able to show the workflow and evidence for a sample of changes end-to-end.

Plain-English interpretation of the requirement

If your SDLC includes manual code reviews before production release for custom software, you must (1) ensure someone other than the author reviews each code change, (2) ensure the reviewer is trained/competent in secure code review, and (3) require an explicit management approval before the change is released to production (PCI DSS v4.0.1 Requirement 6.2.3.1).

Three practical implications:

1. Independence is structural, not a promise. Rely on system controls (pull request rules, branch protection) rather than a policy that people can bypass.
2. Competence must be evidenced. “Senior engineer” is not proof. Keep training records, role definitions, and reviewer assignment logic.
3. Management approval must be tied to release. A weekly CAB note that “we approve changes” is weak unless you can map the approval to the specific release and included commits.

Who it applies to (entity and operational context)

Entities: Merchants, service providers, and payment processors subject to PCI DSS (PCI DSS v4.0.1 Requirement 6.2.3.1).

Operational context (where it bites):

• Teams building or maintaining bespoke or custom software that can affect the cardholder data environment (CDE) or connected systems.
• CI/CD pipelines that deploy to production, including microservices, APIs, batch jobs, infrastructure-as-code modules, and shared libraries, if you treat them as “software changes” in scope for your manual review practice.
• Organizations that claim manual review as part of their secure SDLC controls. Once you represent this control, assessors typically test it through sampling.

Typical owners:

• Engineering (AppSec, Dev leads) owns execution.
• Change management owns release governance and “management approval.”
• GRC/Compliance owns policy requirements, evidence strategy, and audit readiness.

What you actually need to do (step-by-step)

1) Decide and document where manual code review applies

Create a short scoping statement that answers:

• What counts as “bespoke/custom software” in your environment?
• Which repos/services are in scope for this manual review workflow?
• What is your definition of “prior to release to production” (for example: before merge to main, before deployment job runs, before change ticket is closed)?

Keep this in your SDLC standard or secure coding standard so assessors see it as a defined control, not an ad hoc habit.

2) Implement enforced independent review in source control

Configure your repo platform so independence is enforced:

• Require pull/merge requests for changes to protected branches.
• Require at least one approver who is not the PR author.
• Block self-approval and “rubber stamp” patterns (for example: disallow author as approver; restrict who can override).

Evidence objective: show the repo settings (screenshots or exported config) and a change sample with PR metadata proving author ≠ reviewer.

3) Define “knowledgeable reviewer” and make it provable

Create a role definition for “code reviewer” (or “secure code reviewer”) that includes:

• Secure coding practices relevant to your stack.
• Code review techniques (threat-aware review, misuse case thinking, validation of authz/authn, data handling).
• Minimum onboarding/training expectations.

Then implement one of these assignment models:

• Access-based: only trained reviewers are allowed to approve PRs in in-scope repos.
• CODEOWNERS-based: enforce that approvals must come from designated owners with documented competence.
• AppSec-assisted: AppSec reviews specific change types (crypto, auth, payment flows) with documented escalation rules.

Evidence objective: training completion records, secure coding training syllabus, reviewer roster, and PR approval permissions mapping back to the roster.

4) Build a secure code review checklist that matches how engineers work

Avoid a generic checklist nobody reads. Use a short, stack-specific list that reviewers can apply quickly. Example checklist categories:

• Input handling and validation, encoding, deserialization risks.
• Authentication/authorization changes and privilege boundaries.
• Secrets handling (keys, tokens), configuration defaults.
• Logging and error handling (sensitive data, verbosity).
• Dependency and API usage changes that introduce risk.
• Security-relevant tests added/updated (unit tests, negative tests).

Make the checklist required in the PR template or review tool so it becomes part of the evidence trail.

5) Require management approval before production release

This is the part many teams underbuild. Implement a release gate that creates an auditable approval event by management:

• Define who qualifies as “management” for approvals (engineering manager, product owner with change authority, CAB delegate).
• Require that approval is recorded in a system of record (change ticket, release ticket, or deployment approval step).
• Ensure the approval references the specific release (build number, tag, release ID) and links to the PRs/commits included.

Evidence objective: a sampled release record showing management approval timestamped before production deployment, with traceability to the code changes.

6) Connect the dots: traceability from code to release

For each sampled change, you should be able to produce:

• The PR showing author, reviewer, approval, and review notes.
• The linked ticket (feature/bug/change record).
• The release artifact (tag/build) and the management approval record.
• The deployment record (CI/CD log) showing when it hit production.

If your tools are fragmented, Daydream can act as the control hub by collecting PR evidence, change approvals, and training attestations into a single audit-ready packet per release, instead of scrambling across Git, CI, and ITSM during an assessment.

Required evidence and artifacts to retain

Keep evidence that proves each element of the requirement (PCI DSS v4.0.1 Requirement 6.2.3.1):

Independence

• Branch protection / PR rule configuration exports or screenshots.
• PR records for sampled changes showing author and reviewer identities.
• Exception logs (if bypass is possible) and approvals for bypass use.

Reviewer competence

• Secure coding and secure review training records (attendance/completion).
• Role definitions for reviewers and approval permissions.
• Reviewer roster mapped to access controls (who can approve in scope repos).

Management approval before release

• Change/release tickets with approval fields completed by authorized managers.
• CAB or release approval records mapped to the specific release identifier.
• CI/CD approval gates (if used) with approver identity and time.

Traceability

• Links among ticket → PR → build/release → deployment record.
• A sampling worksheet that makes it easy to reproduce the chain for an assessor.

Common exam/audit questions and hangups

• “Show me three recent production changes and prove the reviewer wasn’t the author.” If you can’t pull it quickly from the repo, you will burn time.
• “How do you know reviewers are knowledgeable about secure coding?” Titles and tenure won’t satisfy this on their own; produce training/role evidence.
• “Where is management approval captured, and how do you ensure it happens before release?” Auditors look for timestamps and release linkage.
• “What happens in emergencies?” If you have break-glass, show the exception workflow and retrospective review requirement.

Frequent implementation mistakes and how to avoid them

1. Policy says “peer review,” but branch rules allow direct commits. Fix by enforcing PR-only merges for protected branches.
2. Self-approval allowed “for convenience.” Remove it; independence is explicit in the requirement (PCI DSS v4.0.1 Requirement 6.2.3.1).
3. Management approval happens after deployment in practice. Move approval to a release gate; enforce it in ITSM or CI/CD.
4. No proof of reviewer competence. Maintain a reviewer roster and training records, and restrict approval rights to that roster.
5. Evidence lives in chat. Chat approvals are hard to audit. Route approvals through systems that retain immutable records.

Risk implications (why assessors care)

Manual review is meant to catch security-impacting issues that automation may miss, especially authorization logic, business logic flaws, and dangerous patterns introduced in custom code. Weak review controls raise the likelihood of insecure code reaching production and reduce your ability to demonstrate controlled change practices in the CDE. For PCI programs, that becomes a compliance risk (failure to meet the stated control) and a security risk (higher chance of exploitable defects persisting).

Practical execution plan (30/60/90-day)

Use phases so you can move fast without claiming unrealistic timing.

First 30 days (Immediate)

• Confirm in-scope repos/services for bespoke/custom software subject to manual review (PCI DSS v4.0.1 Requirement 6.2.3.1).
• Turn on PR-based workflow and block direct commits to protected branches for in-scope repos.
• Define “management approval” roles and where the approval will be recorded (ITSM ticket, release ticket, or pipeline gate).
• Publish the minimum secure code review checklist and add it to PR templates.

By 60 days (Near-term)

• Restrict PR approval rights to a trained reviewer set (CODEOWNERS or access groups).
• Roll out secure code review training for reviewers and start retaining completion evidence.
• Implement release traceability: ticket links in PRs, release IDs in tickets, and deployment logs retained.

By 90 days (Operationalize and sustain)

• Run an internal “mock assessment” sampling exercise: pull several recent changes and produce end-to-end evidence.
• Formalize exception handling for emergency changes (break-glass approvals, retrospective review, management sign-off).
• Centralize evidence collection (for example, in Daydream) so each release has a ready-to-export evidence packet.

Frequently Asked Questions

Does PCI DSS 6.2.3.1 require manual code reviews for all software changes?

The text is conditional: “If manual code reviews are performed…” (PCI DSS v4.0.1 Requirement 6.2.3.1). If your program uses manual reviews as a control before production release, you must meet the independence, competence, and management approval conditions.

Who counts as “management” for the approval step?

PCI DSS 6.2.3.1 requires “reviewed and approved by management prior to release” (PCI DSS v4.0.1 Requirement 6.2.3.1). Define “management” in your SDLC/change policy (for example, engineering manager or designated change authority) and ensure approvals are recorded and traceable to the release.

Can a senior engineer approve if they didn’t write the code?

Independence requires the approver is “other than the originating code author” (PCI DSS v4.0.1 Requirement 6.2.3.1). Seniority helps, but you still need evidence they are “knowledgeable about… secure coding practices,” typically via training records and a reviewer role definition.

Are pull request approvals enough to satisfy “management approval”?

PR approvals can satisfy the independent review piece, but “approved by management prior to release” is a separate requirement element (PCI DSS v4.0.1 Requirement 6.2.3.1). Many teams capture management approval in a release/change ticket or a deployment approval gate tied to the production rollout.

How should we handle emergency fixes?

Allow an emergency path only with explicit exception controls: documented reason, logged approver identity, and a required retrospective independent review plus management sign-off (PCI DSS v4.0.1 Requirement 6.2.3.1). Keep the exception evidence with the same traceability as standard changes.

What evidence is most convincing in an audit?

Assessors typically respond well to system-enforced controls: branch protection settings, PR records showing non-author review, training records for reviewers, and a release/change record showing management approval before production deployment (PCI DSS v4.0.1 Requirement 6.2.3.1).