# BSI C5 SSO-02 — Risk assessment of service providers and suppliers

- Source: https://support.icompaas.com/support/solutions/articles/a_gen_bsic5_sso02_5355410630-bsi-c5-sso-02-risk-assessment-of-service-providers-and-suppliers
- Section: [Solutions](https://support.icompaas.com/support/solutions) › [BSI C5 (German Cloud)](https://support.icompaas.com/support/solutions/c_gen_bsi_c5) › [Supplier & Service Oversight](https://support.icompaas.com/support/solutions/folders/f_gen_cgenbsic5_supplierserviceoversight)
- Last updated: 2026-05-30
- Publisher: iCompaas, Inc. (https://www.icompaas.com)

BSI C5 · Control SSO-02 · Priority: high · Component: Supplier & Service Oversight

### What this control covers

Conducts and annually reviews risk assessments for third parties per SSO-01, evaluating confidentiality, integrity, and dependency risks. Documents mitigation measures to ensure secure service delivery and protect cloud customer data.

### Why it matters

Risk is the language an executive team understands; this control connects technical reality to board-level decisions and budget allocation.

### How to implement

#### AWS

Codify the policy intent as **SCPs, AWS Config conformance packs, and Security Hub standards** so the cloud enforces what the document says.

#### Azure

Codify in **Azure Policy initiatives** (built-in regulatory compliance for CIS, ISO 27001, SOC 2, HIPAA) and assign at management-group level.

#### GCP

**Org Policy Service** for guardrails and **Config Validator** in CI to pre-check Terraform plans against policy as code (Rego).

#### Google Workspace

Enforce **2-Step Verification** (preferably hardware keys for admins) for the entire org, set session length to ≤ 12 hours, and disable less-secure-app access. Use **Context-Aware Access** levels to restrict admin sign-in by IP/device posture. Provision and de-provision users via **SCIM** from your HRIS so leavers lose access on day one.

#### GitHub

Require **SSO + SCIM** from your IdP on the organisation; enforce **2FA** org-wide and use **fine-grained PATs** (or, better, GitHub Apps) instead of classic tokens. Restrict **outside collaborators**, require signed commits on protected branches, and use **OIDC** from Actions to short-lived AWS/GCP/Azure credentials rather than stored secrets.

#### Zoho Mail

Make **two-factor authentication** mandatory for all users (TOTP, OneAuth, or YubiKey) in _Admin Console → Security_. Configure **SAML SSO** against your IdP and disable password-based logins for admins. Use **role-based privileges** (Admin / Spam Moderator / Mail Account Admin) and review the _Login history_ report monthly for anomalies.

#### On-premises

Maintain a policy library with a documented review cadence (annual minimum); store in your GRC tool with attestation tracking. Map each policy to controls so an audit pull cites the exact policy clause.

### Evidence to collect

-   `vendor_risk_management` — See the iCompaas Evidence library for the canonical source for this evidence type.

Third-party risk management evidence (assessments, contracts, due diligence) shows supplier oversight. Focus: Risk assessment of service providers and suppliers.

### Quick checklist

-   Risk — Dependency / Measures
-   Security — Dependency / Measures
-   Confidentiality — Dependency / Measures
-   Data — Dependency / Measures
-   Secure — Dependency / Measures

### Related articles on this site

-   [Microsoft Cloud Security Posture Management (CSPM)](https://support.icompaas.com/support/solutions/articles/62000234105-microsoft-cloud-security-posture-management-cspm-)
-   [2.10 Ensure that Microsoft Cloud App Security (MCAS) integration with Security Center is selected](https://support.icompaas.com/support/solutions/articles/62000219760-2-10-ensure-that-microsoft-cloud-app-security-mcas-integration-with-security-center-is-selected)
-   [Source Code Supply Chain Security](https://support.icompaas.com/support/solutions/articles/62000225179-source-code-supply-chain-security)
-   [NIST 800-171 3.2.1 Ensure that managers, systems administrators, and users of organizational systems are made aware of the security risks associated with their activities and of the applicable policies, standards, and procedures related to](https://support.icompaas.com/support/solutions/articles/62000229264-nist-800-171-3-2-1-ensure-that-managers-systems-administrators-and-users-of-organizational-systems-)

## 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.