API identity security gaps are widening as machine access sprawl grows

At a glance

What this is: This is an analysis of why API security is fundamentally an identity problem, with hard-coded secrets, weak inventory practices, and machine identities creating a larger attack surface than many teams can govern.

Why it matters: It matters because IAM and NHI teams need controls for the identities behind APIs, not just the APIs themselves, or they will miss the access paths attackers actually use.

By the numbers:

• 45:1

👉 Read CyberArk's analysis of API identity security and secrets abuse

Context

APIs are the programmatic links that let machines, workloads, and automation exchange data and actions. In practice, that makes them an identity problem as much as an interface problem, because every API that touches protected resources depends on secrets and permissions that must be governed across the full lifecycle.

The risk is not limited to exposed endpoints. Hard-coded keys, unmanaged tokens, and third-party connections create trust paths that attackers can abuse once they find a single valid secret. For IAM and NHI practitioners, the question is whether the organisation can inventory, rotate, and monitor those machine identities at the same pace that development teams create them.

Key questions

Q: How should security teams govern API secrets across cloud and DevOps environments?

A: Security teams should treat API secrets as managed non-human identities, not developer convenience items. That means centralised storage, automated rotation, strict ownership, expiry enforcement, and audit trails across code, pipelines, and runtime systems. The goal is to prevent secrets from becoming durable access paths that outlive the workload or integration that created them.

Q: Why do APIs create identity risk even when the application code is secure?

A: APIs create identity risk because the code can be clean while the credentials behind it remain exposed, over-privileged, or reused. Attackers usually target the secret, not the endpoint. Once they have a valid key or token, they can impersonate the workload and inherit whatever access that identity already has.

Q: What is the difference between API security and NHI governance?

A: API security focuses on protecting the interface and its traffic, while NHI governance focuses on the identities and secrets that authorise machine-to-machine access. The second is broader because it covers lifecycle controls, entitlement scope, ownership, and revocation. In practice, strong API security depends on strong NHI governance.

Q: Should organisations prioritise secret rotation or API inventory first?

A: Organisations should start with inventory if they do not know which APIs and secrets exist, because you cannot rotate what you cannot find. Once the inventory exists, rotation, expiry, and access scoping become measurable controls instead of guesswork. Discovery and lifecycle management should move together, but discovery is the prerequisite.

Technical breakdown

Why API identity and secret exposure become the real attack surface

APIs do not authenticate themselves. They rely on machine identities such as service accounts, API keys, certificates, or tokens to prove who or what is calling a protected service. When those secrets are embedded in code, scripts, CI/CD tools, or public repositories, the access path becomes portable for an attacker. The weakness is usually not the protocol itself but the lifecycle around it: issuance, storage, rotation, and revocation. Once a secret is copied, the attacker can act as the workload that owns it until the credential is detected and replaced.

Practical implication: Treat every API secret as a governed identity artifact with ownership, expiry, and rotation requirements.

Why API inventory failures create blind spots for least privilege

Least privilege only works when teams know which APIs exist, what they call, and what data or services they can reach. In many environments, API sprawl grows faster than cataloguing because engineering teams create interfaces for internal automation, partner access, and product features without a central identity model. That leaves security teams with partial visibility and inconsistent policy enforcement. The result is over-privilege by default, especially where service-to-service trust has grown incrementally over time.

Practical implication: Build an authoritative API and machine identity inventory before tightening authorisation policies.

How centralized secrets management reduces API abuse paths

Centralized secrets management replaces scattered credentials with a controlled system for storage, rotation, distribution, and audit. It does not remove the need for secure design, but it does give security teams one place to enforce policy and observe use across applications, DevOps pipelines, and automation tools. For APIs, that matters because compromise often starts with a credential that should have been ephemeral, rotated, or scoped more narrowly. The control objective is not just secrecy, but reducing the blast radius when a secret is exposed.

Practical implication: Use centralized secrets governance to shorten credential lifetime and narrow access scope across machine-to-machine flows.

Threat narrative

Attacker objective: The objective is to inherit a machine identity with enough privilege to reach data, services, or infrastructure without triggering user-centric controls.

1. Entry occurs when an attacker finds hard-coded API credentials in a script, repository, or exposed integration path.
2. Escalation follows when the stolen secret is accepted as a legitimate machine identity and grants access to data, cloud functions, or administrative actions.
3. Impact occurs when the attacker uses that access to copy databases, alter workloads, or expand into adjacent systems under the same trust model.

Breaches seen in the wild

• Shai Hulud npm malware campaign — Shai Hulud campaign: npm malware exposed secrets on GitHub.
• Reviewdog GitHub Action supply chain attack — reviewdog/action-setup GitHub Action supply chain attack exposed secrets.

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

NHI Mgmt Group analysis

API security is now a machine identity problem, not a perimeter problem. The article describes APIs as communication channels, but the security failure mode sits in the identities and secrets that power them. When credentials become the access primitive, user-centric controls miss the real enforcement point. Practitioners should govern API access as a lifecycle issue spanning issuance, storage, rotation, and revocation.

Identity blast radius is the metric that matters when APIs sprawl faster than inventory. If teams cannot account for every API and its trust relationships, least privilege becomes a partial control at best. The problem is not only exposure, but the number of systems that inherit access once one secret is compromised. Security leaders should reduce how far any single API credential can travel across services and environments.

Static secrets create trust debt that accumulates faster than most security programmes can repay. Hard-coded keys, long-lived tokens, and unmanaged third-party connections turn every shortcut into durable exposure. This is especially true where DevOps pressure encourages convenience over lifecycle discipline. The correct response is to treat secrets as disposable access grants and eliminate standing reliance wherever possible.

API governance must converge with NHI governance if organisations want usable control. The article correctly frames modern APIs as part of machine communication, but that framing should lead to a broader control model that includes service accounts, automation, and application identities. Without that convergence, teams will keep solving syntax-level API issues while missing the access layer. Practitioners should align API programs with NHI governance instead of running them as separate disciplines.

From our research:

• Only 44% of organisations have implemented any policies to manage their AI agents, despite 92% agreeing that governing AI agents is critical to enterprise security, according to The 2026 Infrastructure Identity Survey.
• A separate finding from the same survey shows that 70% of organisations grant AI systems more access than they would give a human employee performing the exact same job.
• For a broader control model, review OWASP NHI Top 10 to align API and agent access governance with current attack patterns.

What this signals

Identity blast radius is becoming the practical measure of API security. As machine identities proliferate, the question is no longer whether an API is authenticated, but how far that credential can travel once it is compromised. With 70% of organisations granting AI systems more access than human employees performing the same job, the broader pattern is clear: machine access is frequently over-scoped before security teams have a governance model in place.

API programmes should now be folded into NHI governance and not treated as a separate engineering hygiene task. That shift matters because secrets, service accounts, and machine permissions all fail in the same way when lifecycle controls are missing. Teams that still rely on static credential habits should use the Ultimate Guide to NHIs as the baseline for ownership, rotation, and offboarding.

Static credential dependence is a signal that policy maturity has not kept pace with automation. The more APIs connect to cloud services, partner systems, and CI/CD workflows, the more the organisation needs explicit control boundaries. Security leaders should prepare for continuous access review, tighter secret scope, and stronger linkage between IAM, DevOps, and application owners.

For practitioners

• Inventory every API and machine identity Create a single inventory that links APIs to owners, secrets, service accounts, data classifications, and downstream permissions. Without that map, policy enforcement and access reviews will be incomplete.
• Centralise secret storage and rotation Move API keys, tokens, and certificates into a controlled secrets system with automatic rotation, audit logging, and expiry enforcement. Prioritise credentials used by production services and DevOps tooling.
• Reduce standing privilege for service-to-service access Scope each credential to the minimum resource set and replace broad, persistent access with task-specific permissions wherever possible. Revalidate high-risk secrets after every application change or integration expansion.
• Measure API and secret exposure as an NHI risk Tie API governance to NHI reviews, because the identity behind the call is what attackers steal. Use findings from The 52 NHI breaches Report and the OWASP NHI Top 10 to pressure-test your control gaps.

Key takeaways

• API security breaks down when machine identities and their secrets are unmanaged across the software lifecycle.
• The scale problem is structural: machine identities and API secrets now outnumber human identities 45:1.
• Organisations need inventory, rotation, and least-privilege controls that follow the secret, not just the endpoint.

Key terms

• Machine Identity: A machine identity is the credentialed representation of a non-human actor such as an application, script, workload, or automation pipeline. It is used to authenticate and authorise programmatic access to services, data, and infrastructure, often through keys, tokens, certificates, or service accounts.
• API Secret: An API secret is a credential that allows a machine or application to access an API. It may be a key, token, password, or certificate. If exposed, reused, or left long-lived, it can be copied by attackers and used to impersonate the original workload.
• Identity Blast Radius: Identity blast radius is the amount of access and downstream impact that a compromised identity can create. In NHI environments, it describes how far a stolen secret can travel across systems, data, and cloud services before detection or revocation limits the damage.
• Secrets Management: Secrets management is the controlled storage, distribution, rotation, and auditing of credentials used by applications and automated systems. It reduces exposure by centralising governance, shortening credential lifetime, and making machine access more observable and revocable.

Deepen your knowledge

API identity governance and secrets lifecycle management are core topics in our NHI Foundation Level course, the industry's only accredited NHI security programme. If your team is trying to bring API security under a repeatable control model, this is a practical place to start.

This post draws on content published by CyberArk: Understanding APIs and How Attackers Abuse Them to Steal Data. Read the original.