Shared Responsibility Model

Expanded Definition

The shared responsibility model is the boundary that separates provider-managed cloud security from customer-managed security. In NHI governance, that boundary matters because platform hardening, physical infrastructure, and many native controls sit with the provider, while the organisation still owns secret placement, privilege design, rotation, monitoring, and offboarding.

Definitions vary across vendors in how far the model extends into managed services, serverless platforms, and identity federation. No single standard governs this yet, so practitioners usually map responsibilities by service type and by control layer rather than assuming a blanket rule. For a standards-based lens, the NIST Cybersecurity Framework 2.0 is useful because it frames governance, protection, detection, and recovery as operational outcomes that still require customer action even when the infrastructure is outsourced. The most common misapplication is treating the cloud provider as the owner of identity risk, which occurs when teams assume native controls replace internal governance.

For NHI security, the model is really about control ownership, not blame allocation. It determines who must review service account permissions, who rotates API keys, who validates access paths, and who responds when secrets appear in code or logs.

Examples and Use Cases

Implementing the shared responsibility model rigorously often introduces operational overhead, requiring organisations to weigh faster cloud adoption against the cost of continuous identity governance.

• A platform team uses a managed database service, but the application owner still controls whether the database credential is stored in a secrets manager or embedded in deployment files.
• A security team assumes the cloud provider monitors all service-account misuse, yet the organisation still needs its own alerting and review process for anomalous token use.
• An engineering group enables federated workload identity, but it remains responsible for role design, expiration policies, and access review because the provider does not validate business intent.
• A compliance team adopts guidance from the NIST Cybersecurity Framework 2.0 to document which detective controls remain internal even when the platform is cloud-hosted.
• Security leaders reference the Ultimate Guide to NHIs when defining who owns rotation, offboarding, and visibility for non-human identities across SaaS and cloud services.

Across these use cases, the model is less about architecture diagrams and more about ensuring that identity duties are explicitly assigned, tested, and auditable.

Why It Matters in NHI Security

Shared responsibility becomes critical because most NHI incidents occur in the customer-controlled layer, where privileges are excessive, secrets are stale, or monitoring is missing. NHI Mgmt Group research shows that Ultimate Guide to NHIs reports that 97% of NHIs carry excessive privileges, which directly reflects customer-side governance gaps rather than provider failure.

This matters because cloud-native teams often assume platform defaults equal security maturity, yet identity abuse usually begins with overbroad access, long-lived credentials, or unreviewed service accounts. The cloud provider may secure the substrate, but it cannot decide whether a workload should still hold production access, whether a token should be revoked after deployment, or whether secrets should be rotated after exposure. That is why the model aligns closely with the operational expectations in the NIST Cybersecurity Framework 2.0, especially around governance and continuous protection. Organisations typically encounter the consequences only after a secret leak, access escalation, or incident review, at which point shared responsibility becomes operationally unavoidable to address.

Related resources from NHI Mgmt Group

• What is the Model Context Protocol (MCP) and why does it matter for security?
• What does AI model abuse reveal about the current NHI threat surface?
• Why do attackers often check model availability before trying to generate content?
• How does automated secret rotation change the operational model?