# BSI C5:2020 PSS-04 — Error handling and Logging Mechanisms - Source: https://support.icompaas.com/compliance/bsi-c5-2020/pss-04-error-handling-and-logging-mechanisms - Section: [Compliance](https://support.icompaas.com/compliance) › [BSI C5:2020 (Cloud Computing Compliance Criteria)](https://support.icompaas.com/compliance/bsi-c5-2020) › Platform & Service Security (PSS) - Last updated: 2026-06-05 - Publisher: iCompaas, Inc. (https://www.icompaas.com) **BSI C5:2020**·Criterion `PSS-04`·high·Component: **Platform & Service Security** ## What this control requires > Equips cloud service with error handling and logging to track access, malfunctions, and configuration changes. Protects logs from unauthorized access, enabling customers to monitor security and ensure cloud data integrity. > > — BSI C5:2020, Criterion PSS-04 ### In plain English Equips cloud service with error handling and logging to track access, malfunctions, and configuration changes. In practice, this means you can prove you security - configuration-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-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. #### Logging Monitoring **AWS.** Org-trail CloudTrail to a central log archive account, GuardDuty in every region, and Security Hub for cross-source correlation. **Azure.** Pipe every diagnostic setting into a central Log Analytics workspace; onboard Microsoft Sentinel for SIEM/SOAR. **GCP.** Aggregate audit logs in a dedicated logging project with sink to BigQuery; enable Security Command Center Premium and route findings to Chronicle SIEM. ### Operational checklist - **Security.** Document the trigger, the owner and the cadence. - **Data.** Document the trigger, the owner and the cadence. - **Access.** Document the trigger, the owner and the cadence. - **Monitor.** Document the trigger, the owner and the cadence. - **Error.** Document the trigger, the owner and the cadence. - **Scope:** - configuration, mechanisms, changes, 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: Error handling and Logging Mechanisms. ## 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. - Per-account logging that nobody stitches together at the org level — incidents that cross accounts go undetected for days. - 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 3.13.6** — Network Communications - Deny by Default - Allow by Exception](https://support.icompaas.com/compliance/nist-sp-800-171-rev-3/3-13-6-network-communications-deny-by-default-allow-by-exception) - [**NIST SP 800-53 Rev. 5 AU-5(1)** — Storage Capacity Warning](https://support.icompaas.com/compliance/nist-sp-800-53-rev-5/au-5-1-storage-capacity-warning) - [**CIS Controls v8 13.1** — Centralize Security Event Alerting](https://support.icompaas.com/compliance/cis-controls-v8/13-1-centralize-security-event-alerting) - [**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) ## Related controls in BSI C5:2020 - [**Criterion PSS-06** — Session Management](https://support.icompaas.com/compliance/bsi-c5-2020/pss-06-session-management) - [**Criterion PSS-01** — Guidelines and Recommendations for Cloud Customers](https://support.icompaas.com/compliance/bsi-c5-2020/pss-01-guidelines-and-recommendations-for-cloud-customers) - [**Criterion OPS-14** — Logging and Monitoring - Storage of the Logging Data](https://support.icompaas.com/compliance/bsi-c5-2020/ops-14-logging-and-monitoring-storage-of-the-logging-data) - [**Criterion OPS-12** — Logging and Monitoring - Access, Storage and Deletion](https://support.icompaas.com/compliance/bsi-c5-2020/ops-12-logging-and-monitoring-access-storage-and-deletion) - [**Criterion INQ-02** — INQ-02 Informing Cloud Customers about Investigation Requests](https://support.icompaas.com/compliance/bsi-c5-2020/inq-02-inq-02-informing-cloud-customers-about-investigation-requests) - [**Criterion OPS-16** — Logging and Monitoring - Configuration](https://support.icompaas.com/compliance/bsi-c5-2020/ops-16-logging-and-monitoring-configuration) ## 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 PSS-04` Topics: logging monitoringcloud infrastructurecloud postureconfiguration 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.