BSI C5:2020·Criterion PSS-02·high·Component: Platform & Service Security

What this control requires

Checks cloud service for vulnerabilities during development using static/dynamic testing and code reviews. Assesses severity and mitigates risks promptly, ensuring robust protection of cloud customer data from software-related weaknesses.
— BSI C5:2020, Criterion PSS-02

In plain English

Checks cloud service for vulnerabilities during development using static/dynamic testing and code reviews. In practice, this means you can prove you application protection-level controls on a defined cadence.

Why it matters

BSI C5 is the default cloud-security baseline German public-sector buyers and many DAX-listed enterprises expect; gaps here directly block procurement in the DACH region and frequently appear as must-have items in EU public-tender documents.

This control is rated high. Auditors expect a named owner, a remediation SLA, and a tooling artefact that evidences continuous operation.

What an auditor looks for

A C5 attesting auditor (under ISAE 3000 / IDW PS 860) tests both the design and — for a Type 2 — the operating effectiveness over the attestation period. For each criterion they look for both the Basic and any in-scope Additional objectives.

Within Platform & Service Security, the assessor will trace your implementation back to the catalogue reference (Criterion PSS-02) and look for objective evidence on the latest two assessment cycles.

How to implement

Code Review Testing

Pipeline. Require at least one human reviewer plus passing CI (lint, type, unit, security scan) before merge — protected branches enforce this.

Secure Development

Pipeline. Require code review, SAST (Semgrep / Snyk Code), SCA (Dependabot / Renovate), secret-scanning and IaC scanning in the merge pipeline.

Branch protection. Protected branches enforce reviews, signed commits and passing CI before merge; document the protection rules as the control evidence.

Cloud Posture

CSPM. Run Wiz / Prisma / Defender for Cloud / Security Command Center over every account; auto-ticket findings above your accepted-risk threshold.

Operational checklist

  • Application. Document the trigger, the owner and the cadence.
  • Review. Document the trigger, the owner and the cadence.
  • Security. Document the trigger, the owner and the cadence.
  • Protection. Document the trigger, the owner and the cadence.
  • Data. Document the trigger, the owner and the cadence.
  • Scope: protection, cloud customer data, development.

Evidence to collect

  • Code Repo Scan. Source-control evidence — branch protection, required reviewers, CI status, SCA / SAST reports.

Source control pipelines (GitHub, GitLab) enforce SDLC guardrails. Focus: Identification of Vulnerabilities of the Cloud Service.

Common pitfalls

  • CI security checks set to warn-only; the merge button is faster than the security feedback.
  • Treating CSPM findings as a backlog instead of a hot queue: findings older than the policy SLA accumulate until the auditor asks why.

How it maps to other frameworks

Computed from shared tags, control component and key-operation subjects — handy when you are reconciling controls across an audit.

Related controls in BSI C5:2020

References

Topics: application securitysecure developmentcode review testingdevsecopscloud posture