Azure shared key flaws expose secret trust assumptions in cloud IAM

At a glance

What this is: This is an analysis of an Azure shared-key authorization flaw that can expose secrets and enable privilege abuse through storage accounts and managed identities.

Why it matters: It matters because cloud IAM, NHI governance, and secrets management teams need controls that cover exposure, delegation, and offboarding, not just vault placement.

By the numbers:

• 44% of NHI tokens are exposed in the wild, being sent or stored over platforms like Teams, Jira tickets, Confluence pages, and code commits.

👉 Read Entro Security's analysis of the Azure shared key authorization flaw

Context

Azure shared key authorization is a cloud access pattern that gives storage account keys broad control over data and configuration. The governance problem is not storage alone, but the fact that a shared key can become a standing trust bypass when it is reachable through a lower-privileged path.

In identity terms, this is an NHI problem first and a cloud architecture problem second. If a storage-backed function can be manipulated to expose higher-privileged credentials, the real failure is that secret access, workload identity, and lateral movement are too tightly coupled for the security model to absorb.

For IAM and secrets teams, the important question is whether the control plane assumes that a credential stays confined to the role that originally issued it. This article shows why that assumption can fail once shared keys and managed identities intersect.

Key questions

Q: What breaks when storage account keys can influence workload identity?

A: The boundary between data access and privilege control breaks down. A storage key or adjacent contributor role can become a path to token theft, lateral movement, and broader cloud compromise if the workload runtime can be altered. Teams should treat any credential that can affect execution as a high-risk identity control issue, not a simple storage permission problem.

Q: Why do shared keys create more risk than scoped authentication in cloud storage?

A: Shared keys concentrate authority into one credential that often outlives the original task and can affect multiple actions. Scoped authentication, such as identity-based access, reduces the size of the trust boundary and makes misuse easier to contain. The difference is not convenience versus complexity, but whether the credential can be abused as standing privilege.

Q: What do security teams get wrong about managed identities in Azure?

A: They often assume managed identity removes the need to govern the execution path around it. In reality, if storage, code, or deployment content can be rewritten, the identity can still be abused indirectly. The control problem is not only the identity itself, but every component that can influence how that identity is used.

Q: Who is accountable when a storage-backed function exposes higher-privileged credentials?

A: Accountability sits across cloud platform, application, and IAM teams because the failure crosses access, runtime integrity, and secret governance. The right control model assigns ownership to the workload path, the storage resource, and the identity issuer rather than treating the incident as a single-team problem.

Technical breakdown

Shared key authorization creates a broad trust boundary

Azure storage account shared key authorization uses account-level keys that can authenticate access to both data and configuration. When a single secret can authorize multiple actions, the security boundary moves from a scoped token to the whole storage account. That makes the key itself a high-value NHI credential, not a narrow application secret. The risk is amplified when the same key also supports SAS token creation, because delegation can spread through downstream workloads without visible ownership change. In practice, the issue is not only exposure, but the oversized authority attached to one credential.

Practical implication: remove any standing access path that lets one storage key govern both data access and configuration control.

Function app storage can become a credential theft pivot

The article describes an attacker with Storage Account Contributor access overriding function files in storage to steal higher-privileged identity tokens. That is a classic pivot from resource-level permission to credential acquisition. Once the function runtime is manipulated, the attacker is no longer just reading data. They are using the storage-backed execution path to impersonate a stronger identity and extend authority into the subscription. This is why service-to-service identity needs tighter separation between code, storage, and the permissions used to run the workload.

Practical implication: isolate function storage from identities that can rewrite executable content or harvest tokens.

Managed identity abuse can turn one compromise into lateral movement

A managed identity is meant to reduce secret handling, but it still becomes a credential if the workload path that uses it can be subverted. In this case, a compromised function can acquire a higher-privileged identity and then move laterally into other Azure resources. That later stage is where cloud compromise often broadens into operational impact, including malware deployment or ransomware. The technical lesson is that workload identity inherits the blast radius of every component that can influence its runtime or token flow.

Practical implication: review which storage, code, and execution components can indirectly reach managed identity tokens.

Threat narrative

Attacker objective: The attacker wants to convert a low-privilege storage foothold into high-privilege cloud access that can be used for lateral movement and destructive actions.

1. Entry occurs when an attacker gains access to a storage account path tied to an Azure Function that can influence shared-key-backed content or configuration.
2. Escalation follows when the attacker overrides function files to steal tokens from a higher-privileged managed identity and use that identity beyond the original scope.
3. Impact is achieved when the attacker moves laterally, accesses crown-jewel resources, and can execute malware, reverse shells, or ransomware.

Breaches seen in the wild

• 230M AWS environment compromise — 230M AWS environments compromised via exposed .env files with cloud credentials.
• Google Firebase misconfiguration breach — Firebase misconfigurations exposed 19.8M secrets across developer instances.

Read our 52 NHI Breaches Analysis report for a comprehensive view of breaches impacting Non-Human Identities including AI Agents.

NHI Mgmt Group analysis

Shared key authorization is a standing privilege problem disguised as convenience. The article shows that one storage credential can authorize configuration changes, data access, and downstream token abuse. That is not a narrow secret management issue but a trust-boundary failure in cloud IAM design. Practitioners should treat any shared key that can influence runtime or configuration as a high-risk standing privilege.

Managed identity does not eliminate secret risk when the execution path is mutable. The managed identity in this scenario becomes unsafe because the function runtime and storage files can be altered to capture its token. This is the kind of failure mode OWASP-NHI and NIST CSF both try to surface: identity controls break when the workload path can redirect authority. The implication is that workload identity governance must include runtime integrity, not only credential issuance.

Azure Function storage creates an identity blast radius when code and secrets share the same control plane. Once a storage-backed function can be modified by a contributor role, the attacker can inherit much more privilege than the role appears to grant. That makes the relevant governance concept an identity blast radius, where a single weakly governed component determines how far credential abuse can spread. Practitioners should map where code, storage, and identity meet, because that junction often defines the real attack surface.

This flaw reinforces that secrets governance must follow the secret across its lifecycle, not just at rest. The article is a reminder that creation, storage, reuse, and runtime use all matter when a credential can be consumed by a workload. In NHI terms, lifecycle control is the missing discipline when secret ownership and execution authority diverge. Teams should therefore govern where secrets can travel, not only where they are stored.

Cloud privilege boundaries collapse faster when access paths can both read and rewrite trust material. A Storage Account Contributor role sounds limited until it can manipulate a function that later reveals stronger credentials. That is a classic example of indirect privilege amplification, where one role becomes a bridge to another identity class. Security teams should re-evaluate any architecture where storage, execution, and identity are not separately controlled.

From our research:

• 91% of former employee tokens remain active after offboarding, leaving organisations vulnerable to potential security breaches, according to The 2025 State of NHIs and Secrets in Cybersecurity.
• Our research also found that 62% of all secrets are duplicated and stored in multiple locations, which increases accidental exposure and complicates ownership across cloud and collaboration tools.
• For a broader control view, review Guide to the Secret Sprawl Challenge to connect exposure, lifecycle, and remediation into one operating model.

What this signals

Storage-backed workload identity is becoming a governance boundary, not just an implementation detail. When secret material can affect both configuration and execution, teams need to model the whole runtime path in their identity programme, especially where Azure functions, shared keys, and managed identities intersect.

Identity blast radius: the real risk is how far a single credential can travel once code, storage, and identity are coupled. Practitioners should use this incident to revisit which workloads can rewrite their own trust material and whether those paths are visible in access reviews.

For teams aligning to modern identity guidance, the issue maps cleanly to OWASP Non-Human Identity Top 10 and the cloud privilege assumptions behind zero trust. That means revisiting not only secret storage, but also who can change the code that consumes the secret.

For practitioners

• Disable shared key authorization where feasible Prefer Azure Active Directory authentication for storage access and remove any reliance on account-wide shared keys for normal operations.
• Separate function code from token-bearing storage paths Ensure that contributors who can manage storage content cannot alter files that the runtime uses to bootstrap or retrieve privileged identity material.
• Map every workload identity to its writable dependencies Identify which storage accounts, deployment paths, and configuration stores can indirectly influence a managed identity token or execution context.
• Review storage contributor roles for privilege amplification Reassess any role that can rewrite function content, expose secrets, or affect subscription-level access through an attached workload.

Key takeaways

• The Azure flaw shows how a shared storage key can become a privilege-escalation bridge rather than a simple access method.
• The practical risk is not limited to secret exposure, because the attack path can extend into lateral movement, remote code execution, and ransomware.
• Disabling shared key authorization and separating writable code paths from privileged identity material are the controls most likely to reduce blast radius.

Key terms

• Shared Key Authorization: An access model where a single storage account key can authorise broad actions against a cloud storage resource. It is efficient for administration, but it creates a large trust boundary because anyone who obtains the key may inherit configuration and data access at the same time.
• Managed Identity: A cloud-native identity issued to a workload so it can access services without embedding long-lived secrets in code. The security value depends on the integrity of the runtime path, because the identity can still be abused if the workload or its supporting storage is tampered with.
• Identity Blast Radius: The amount of damage an identity compromise can cause before the issue is contained. In cloud environments, blast radius depends on how far a credential can move across services, whether the workload can rewrite trust material, and how much privilege is attached to the execution path.

What's in the full article

Entro Security's full blog covers the operational detail this post intentionally leaves for the source:

• The specific Azure storage and function workflow that lets a contributor role pivot into credential theft
• Microsoft's recommended mitigation path for shared key authorization and Azure Active Directory authentication
• Implementation context for secrets discovery, vault coverage, and anomaly monitoring across cloud-native estates
• Practical examples of how laterally moved identities can be detected before destructive actions begin

👉 Entro Security's full post covers the storage-to-identity attack path and the mitigation options in more operational detail.

Deepen your knowledge

NHI governance, agentic AI identity, and machine identity lifecycle are core topics in our NHI Foundation Level course, the industry's only accredited NHI security programme. If you are responsible for identity security strategy or NHI governance in your organisation, it is worth exploring.