BSI C5:2020 SIM-04 — Duty of the users to report security incidents to a central body

What this control requires

Obliges employees and partners to report security events to a central CSP office, ensuring no penalties for false reports. Facilitates rapid incident detection, protecting cloud customer data through timely response and mitigation efforts.

In plain English

Obliges employees and partners to report security events to a central CSP office, ensuring no penalties for false reports. In practice, this means you can prove you risk duty-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 Security Incident Management, the assessor will trace your implementation back to the catalogue reference (Criterion SIM-04) and look for objective evidence on the latest two assessment cycles.

How to implement

Incident Response

Runbook. Maintain a runbook keyed by incident type with named roles (IC, comms, scribe), an out-of-band comms channel, and a 72-hour timeline for external notification.

Tabletop. Run a quarterly tabletop exercise (ransomware, insider, supply-chain) and feed gaps back into the runbook.

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

• Risk. Document the trigger, the owner and the cadence.
• Security. Document the trigger, the owner and the cadence.
• Data. Document the trigger, the owner and the cadence.
• Duty. Document the trigger, the owner and the cadence.
• Scope: duty, cloud customer data, security incident management, security incidents.

Evidence to collect

• Ticketing Workflow. ticketing_workflow evidence

Workflow metrics (ServiceNow, Jira) show approvals and remediation. Focus: Duty of the users to report security incidents to a central body.

Common pitfalls

• Runbooks that name a role but no person, or list a paging channel that no longer exists.
• 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.

• ISO/IEC 27001:2022 A.5.27 — Learning from information security incidents
• NIST SP 800-53 Rev. 5 IR-6 — Incident Reporting
• CIS Controls v8 17.9 — Establish and Maintain Security Incident Thresholds
• NIST SP 800-171 Rev. 3 3.6.2 — Incident Monitoring, Reporting, and Response Assistance
• SOC 2 (2017 TSC) CC7.4 — Incident Response

Related controls in BSI C5:2020

• Criterion SIM-01 — Policy for security incident management
• Criterion SIM-05 — Evaluation and learning process
• Criterion SIM-02 — Processing of security incidents
• Criterion SIM-03 — Documentation and reporting of security incidents
• Criterion OPS-15 — Logging and Monitoring - Accountability
• Criterion HR-03 — Security training and awareness programme

References

• Bundesamt für Sicherheit in der Informationstechnik (BSI) — BSI C5:2020
• Catalogue identifier: Criterion SIM-04

Topics: incident responsevendor riskchange managementcloud posture