Identity security gaps expose why least privilege still fails

At a glance

What this is: This is Zluri’s overview of identity security, arguing that modern IAM programmes fail when they stop at authentication and do not govern access scope, rotation, monitoring, and offboarding.

Why it matters: It matters because IAM teams have to secure human, NHI, and service identity paths together, or risk leaving the same compromise pattern available across every access layer.

By the numbers:

• stolen credentials cause 86% of breaches
• compromised identities are the first step in 80% of breaches
• only 5.7% of organisations have full visibility into their service accounts
• 97% of NHIs carry excessive privileges

👉 Read Zluri's analysis of why identity security matters for IAM teams

Context

Identity security is the discipline of verifying who or what is accessing systems, then limiting what that identity can do once it is inside. In practice, the article argues that the real problem is not authentication alone but the governance gap between access approval, access scope, and ongoing oversight across human users, service accounts, and machine identities.

That framing fits modern IAM programmes because identity compromise now moves across human and non-human paths with the same basic logic: obtain credentials, inherit privilege, and stay undetected long enough to cause damage. For practitioners, the question is not whether to secure identities, but whether current controls actually constrain standing access, third-party access, and privileged execution.

For a broader governance baseline, the NHI Lifecycle Management Guide and the OWASP Non-Human Identity Top 10 are the right references when identity security starts to touch service accounts, APIs, and workload credentials.

Key questions

Q: What breaks when identity security only verifies login and not access scope?

A: Login verification alone does not stop a valid identity from being overused after entry. If entitlement scope, privilege review, and session control are weak, a compromised account can move through systems with trusted access. Identity security has to govern what the identity can do, not just whether it is real.

Q: Why do service accounts increase breach risk in IAM programmes?

A: Service accounts often carry persistent access, broad entitlements, and weak ownership, which makes them easy to miss in review cycles. When credentials are reused across automation and infrastructure, one compromise can open multiple systems. That is why service account governance is a core IAM control, not a niche operational task.

Q: How do security teams know whether identity security is actually working?

A: Identity security is working when access is narrow, reviewed, and quickly revocable across both human and non-human identities. Strong signals include low standing privilege, visible ownership of accounts, regular rotation of secrets, and evidence that excessive access is removed before it becomes abuse.

Q: Who is accountable when third-party or machine access is over-privileged?

A: The business owner of the access, the system owner, and the identity governance function all share accountability. Third-party and machine access should never be treated as unmanaged convenience layers. If no one can explain why access still exists, the programme has already lost control of the entitlement.

Technical breakdown

Why identity security fails when it stops at authentication

Authentication proves that an identity can get in, but it does not control what happens after entry. Identity security has to pair authentication with authorisation, entitlement scoping, and continuous review. Without that second layer, a valid credential becomes a broad access path rather than a narrow trust decision. The article’s core point is that modern environments need identity controls that follow the session, not just the login event, because attackers rarely need to defeat authentication if they can reuse valid access.

Practical implication: review whether your identity stack enforces least privilege after login, not just strong login factors.

Service accounts, machine identities, and excess privilege

Service accounts and machine identities are non-human identities, but they behave differently from human users because they often run with persistent privileges and no natural offboarding event. That makes them high-value targets for abuse, especially when credentials are embedded in code, scripts, or automation. The article highlights why RBAC alone is not enough if the role itself is oversized. Identity security for NHIs depends on discovery, scope reduction, and rotation discipline, not just policy labels.

Practical implication: inventory non-human accounts and reduce any access that exists only because the role was never revisited.

Zero trust and identity security are complementary, not identical

Zero trust is the architectural principle that nothing is trusted by default, while identity security is the mechanism that verifies and governs each identity’s access. The article treats identity security as foundational to zero trust because continuous verification only works if entitlement, device, and request context are actually enforced. In other words, zero trust without identity governance becomes posture language without operational control.

Practical implication: map your identity controls to zero trust enforcement points and close any gap between policy and actual access decisions.

Threat narrative

Attacker objective: The attacker wants to turn trusted identity into unrestricted access so data theft and internal movement look legitimate to the environment.

1. Entry occurs when attackers obtain valid credentials through identity theft, phishing, exposed secrets, or other compromise paths that bypass perimeter controls.
2. Escalation happens when those credentials carry excessive privilege, allowing the attacker to expand access, move into sensitive systems, or abuse service and machine identities.
3. Impact follows when the attacker uses legitimate identity paths to steal data, persist in the environment, or control high-value access without triggering obvious alarms.

Breaches seen in the wild

• Cisco DevHub NHI breach — IntelBroker exploited exposed Cisco credentials, API tokens and keys in DevHub.
• DeepSeek breach — DeepSeek breach exposed 1M+ log lines and sensitive secret keys.

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

NHI Mgmt Group analysis

Identity security has become an access-governance problem, not just an authentication problem. The article is strongest when it moves beyond login controls and into entitlement scope, privileged execution, and lifecycle oversight. That is where modern IAM programmes either contain identity abuse or silently enable it. Practitioners should treat authentication as the entry condition and governance as the real control plane.

Service accounts are where identity security often fails first because persistence beats review cadence. Non-human identities do not naturally offboard, complain, or prompt recertification, so their risk accumulates quietly. When privilege is embedded in automation, the control failure is usually not visibility alone but the absence of a lifecycle model that can keep pace with machine access. Practitioners should assume any unreviewed service account is a latent privilege multiplier.

Zero trust only works when identity scope is reduced before the request is made. The article correctly connects identity security to zero trust, but the deeper point is that trust assumptions collapse when privileged access is already standing and reusable. That makes identity security the prerequisite for zero trust enforcement rather than a substitute for it. Practitioners should measure whether their zero-trust design actually limits identity blast radius or merely authenticates it.

Identity blast radius is the right concept for explaining why credential compromise keeps turning into large incidents. Once an identity can reach too many systems, one stolen secret becomes a broad internal foothold. That is true across human, vendor, and machine access, which is why governance teams should think in terms of blast radius, not just account inventory. Practitioners should use the concept to prioritise which identities deserve the fastest reduction in privilege.

Least privilege degrades fastest where third-party access and non-human access overlap. The article’s third-party and machine identity discussion points to a common governance weakness: access is granted for collaboration or automation, then left in place after the original need changes. That is how identity risk becomes structural rather than exceptional. Practitioners should treat external and machine access as the first place to test whether least privilege still holds in practice.

From our research:

• 91.6% of secrets remain valid five days after the targeted organisation is notified, showing a critical gap in remediation procedures, according to the Ultimate Guide to NHIs.
• Only 20% have formal processes for offboarding and revoking API keys, and even fewer have procedures for rotating them, according to the Ultimate Guide to NHIs.
• For a deeper lifecycle lens, the NHI Lifecycle Management Guide shows how provisioning, rotation, and offboarding break down when identities are treated as static assets.

What this signals

Identity security programmes will be judged less by authentication strength and more by how quickly they can reduce blast radius after compromise. The practical signal is whether humans, vendors, and machine identities all have explicit owners, narrow entitlements, and revocation paths that actually work in production.

Secret governance is becoming a real-time discipline, not an annual audit activity. When credentials remain valid after exposure, the control failure is lifecycle latency. Teams should expect pressure to move from periodic cleanup toward continuous discovery, rotation, and offboarding across identity classes.

The next maturity step is to connect identity security with access review, PAM, and third-party governance in one operating model, then benchmark it against the NIST Cybersecurity Framework 2.0 and the OWASP Non-Human Identity Top 10.

For practitioners

• Map identity control coverage by actor type Separate human users, third-party accounts, service accounts, and machine identities, then test whether each has a clear owner, approval path, and review cycle. Use the NHI Lifecycle Management Guide to compare lifecycle discipline across these identity classes.
• Reduce standing privilege before expanding automation Identify privileged accounts that can reach sensitive data, cloud control planes, or administrative functions without just-in-time elevation. Remove any access that persists only because the entitlement was never re-evaluated.
• Audit secrets embedded in code and scripts Search source repositories, configuration files, and CI/CD pipelines for long-lived credentials, then replace them with centrally managed secrets and rotation controls. Prioritise identities that can be used without additional human approval.
• Tie zero-trust checks to entitlement drift Use continuous monitoring to detect when identity access expands beyond the original business purpose, especially for vendor access and automation accounts. Align that review with the OWASP Non-Human Identity Top 10 to close common machine-identity failure modes.

Key takeaways

• Identity security fails when access remains broad after authentication succeeds, because the real risk sits in entitlement scope and review discipline.
• Non-human identities make the problem harder because service accounts and machine credentials persist, accumulate privilege, and evade normal user lifecycle controls.
• The practical response is to shrink blast radius by tightening ownership, rotation, revocation, and zero-trust enforcement across every identity type.

Key terms

• Identity Security: Identity security is the set of controls that verifies an identity and limits what that identity can do after access is granted. It combines authentication, authorisation, privilege management, and monitoring so that valid credentials do not become unchecked internal reach.
• Non-Human Identity: A non-human identity is any machine or workload credential used by software, services, or automation to access systems. That includes service accounts, API keys, tokens, certificates, and workload identities, all of which need ownership, lifecycle control, and review.
• Least Privilege: Least privilege means granting only the minimum access required for a task and nothing more. In identity security, that principle must be applied continuously, because access that was once appropriate can become excessive as systems, roles, and integrations change.
• Standing Privilege: Standing privilege is persistent elevated access that remains available without just-in-time approval or temporary scoping. It is risky because it gives attackers or insiders immediate administrative reach once an account or secret is compromised.

Deepen your knowledge

NHI governance, agentic AI identity, machine identity security, IAM, and secrets management 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 governance in your organisation, it is worth exploring.

This post draws on content published by Zluri: Access Management Identity Security: Why Does It Matter? Read the original.