BSI C5:2020 SSO-05 — Exit strategy for the receipt of benefits

What this control requires

Defines exit strategies for high-dependency third-party services, detailing transition costs, roles, and success criteria. Aligns with continuity plans to ensure service continuity and protect cloud customer data during provider transitions.

In plain English

Defines exit strategies for high-dependency third-party services, detailing transition costs, roles, and success criteria. In practice, this means you can prove you risk dependency-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 Supplier & Service Oversight, the assessor will trace your implementation back to the catalogue reference (Criterion SSO-05) and look for objective evidence on the latest two assessment cycles.

How to implement

Business Continuity

BC/DR. Define RTO/RPO per service, test backup restoration quarterly, and run a tabletop of full-region failover annually.

Backups. Immutable backups (S3 Object Lock / Azure immutable storage / GCS bucket lock) plus an air-gapped copy for ransomware resilience.

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.
• Exit. Document the trigger, the owner and the cadence.
• Business. Document the trigger, the owner and the cadence.
• Scope: dependency, cloud customer data, business continuity, management.

Evidence to collect

• Vendor Risk Management. vendor_risk_management evidence

Third-party risk management evidence (assessments, contracts, due diligence) shows supplier oversight. Focus: Exit strategy for the receipt of benefits.

Common pitfalls

• DR plans that have never been tested in earnest, or that depend on an MFA token only one person can produce.
• 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.

• SOC 2 (2017 TSC) CC9.2 — Vendor Risk Management

Related controls in BSI C5:2020

• Criterion SSO-02 — Risk assessment of service providers and suppliers
• Criterion SSO-01 — Policies and instructions for controlling and monitoring third parties
• Criterion SSO-03 — Directory of service providers and suppliers
• Criterion SSO-04 — Monitoring of compliance with requirements
• Criterion COS-03 — Monitoring of connections in the Cloud Service Provider's network
• Criterion BCM-02 — Business impact analysis policies and instructions

References

• Bundesamt für Sicherheit in der Informationstechnik (BSI) — BSI C5:2020
• Catalogue identifier: Criterion SSO-05

Topics: vendor riskvendor managementsupply chain securitybusiness continuitycloud posture