# BSI C5:2020 CRY-04 — Secure key management - Source: https://support.icompaas.com/compliance/bsi-c5-2020/cry-04-secure-key-management - Section: [Compliance](https://support.icompaas.com/compliance) › [BSI C5:2020 (Cloud Computing Compliance Criteria)](https://support.icompaas.com/compliance/bsi-c5-2020) › Cryptography & Key Management (CRY) - Last updated: 2026-06-05 - Publisher: iCompaas, Inc. (https://www.icompaas.com) **BSI C5:2020**·Criterion `CRY-04`·high·Component: **Cryptography & Key Management** ## What this control requires > Implements secure key management for generation, storage, distribution, and deletion, separating key systems from applications. Specifies handling of compromised keys and pre-shared key provisions, protecting cloud customer data encryption integrity. > > — BSI C5:2020, Criterion CRY-04 ### In plain English Implements secure key management for generation, storage, distribution, and deletion, separating key systems from applications. In practice, this means you can prove you security 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 **Cryptography & Key Management**, the assessor will trace your implementation back to the catalogue reference (Criterion CRY-04) and look for objective evidence on the latest two assessment cycles. ## How to implement #### Cloud Posture **CSPM.** Run Wiz / Prisma / Defender for Cloud / Security Command Center over every account; auto-ticket findings above your accepted-risk threshold. #### Configuration Management **Policy-as-code.** Codify the control as Service Control Policies (AWS), Azure Policy initiatives, or Organisation Policy (GCP) so the platform enforces what the document promises. **IaC.** Gate Terraform / Pulumi / CloudFormation changes with Checkov / tfsec / OPA so misconfigurations never reach production. **Drift.** Run a CSPM (Wiz / Prisma / Defender for Cloud / Security Command Center) over every account and route findings to a single risk register. #### Network Security **AWS.** VPC Flow Logs to S3, default-deny security groups, AWS Network Firewall for north-south, and Transit Gateway for hub-and-spoke segmentation. **Azure.** NSGs with deny-by-default, Azure Firewall Premium with TLS inspection, Private Endpoints for PaaS, and Microsoft Defender for Cloud's secure score for drift. **GCP.** VPC Service Controls perimeters around sensitive APIs, Cloud NGFW Enterprise for L7 inspection, Private Service Connect for managed services. ### Operational checklist - **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. - **Encryption.** Document the trigger, the owner and the cadence. - **Secure.** Document the trigger, the owner and the cadence. - **Scope:** protection, - configuration, cloud customer data, key management. ## Evidence to collect - **Infra Scan.** Continuous infrastructure-posture telemetry — AWS Config, Azure Policy compliance, GCP Organisation Policy, Wiz / Prisma findings. Infrastructure posture tooling (AWS Config, Azure Policy, Nessus) verifies platform hardening. Focus: Secure key management. ## Common pitfalls - Treating CSPM findings as a backlog instead of a hot queue: findings older than the policy SLA accumulate until the auditor asks why. - Manual cloud-console changes that never make it back to Terraform — drift accumulates until the next outage forces a reconciliation. - Default-allow egress rules; East-West traffic with no segmentation; jump hosts on the public internet with password auth. ## 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. - [**NIST SP 800-171 Rev. 3 3.14.8** — Information Management and Retention](https://support.icompaas.com/compliance/nist-sp-800-171-rev-3/3-14-8-information-management-and-retention) - [**NIST SP 800-53 Rev. 5 CP-9(3)** — Separate Storage For Critical Information](https://support.icompaas.com/compliance/nist-sp-800-53-rev-5/cp-9-3-separate-storage-for-critical-information) - [**ISO/IEC 27001:2022 A.5.34** — Privacy and protection of personal identifiable information (PII)](https://support.icompaas.com/compliance/iso-27001-2022/a-5-34-privacy-and-protection-of-personal-identifiable-information-pii) - [**CIS Controls v8 11.3** — Protect Recovery Data](https://support.icompaas.com/compliance/cis-controls-v8/11-3-protect-recovery-data) ## Related controls in BSI C5:2020 - [**Criterion CRY-03** — Encryption of sensitive data for storage](https://support.icompaas.com/compliance/bsi-c5-2020/cry-03-encryption-of-sensitive-data-for-storage) - [**Criterion CRY-02** — Encryption of data for transmission (transport encryption)](https://support.icompaas.com/compliance/bsi-c5-2020/cry-02-encryption-of-data-for-transmission-transport-encryption) - [**Criterion OIS-02** — Information Security Policy](https://support.icompaas.com/compliance/bsi-c5-2020/ois-02-information-security-policy) - [**Criterion CRY-01** — Policy for the use of encryption procedures and key management](https://support.icompaas.com/compliance/bsi-c5-2020/cry-01-policy-for-the-use-of-encryption-procedures-and-key-management) - [**Criterion COS-04** — Cross-network access](https://support.icompaas.com/compliance/bsi-c5-2020/cos-04-cross-network-access) - [**Criterion INQ-01** — Legal Assessment of Investigative Inquiries](https://support.icompaas.com/compliance/bsi-c5-2020/inq-01-legal-assessment-of-investigative-inquiries) ## References - [Bundesamt für Sicherheit in der Informationstechnik (BSI) — BSI C5:2020](https://www.bsi.bund.de/EN/Topics/CloudComputing/Compliance_Criteria_Catalogue/Compliance_Criteria_Catalogue_node.html) - Catalogue identifier: `Criterion CRY-04` Topics: data protectioncloud infrastructurecloud postureconfiguration managementkey managementnetwork security ## Related compliance guidance - [SOC 2 compliance: a practical implementation guide for cloud-native SaaS teams](https://support.icompaas.com/compliance/soc-2-trust-services-criteria): Configuration checks like this one are the technical half of a SOC 2 / ISO 27001 programme — the guide shows where they fit, what else an auditor expects, and how to evidence them. - [ISO/IEC 27001:2022 compliance: a practical implementation guide](https://support.icompaas.com/compliance/iso-27001-2022): ISO 27001 Annex A.8 (technological controls) is where cloud hardening evidence lands; the guide shows how to run the ISMS around it.