Identity-first zero trust: why CISOs must center machine identities

At a glance

What this is: This is an identity-first Zero Trust analysis that says machine identities and credentials have become the main control point because attackers can bypass perimeter defences with valid access.

Why it matters: It matters because IAM, PAM, and NHI programmes now determine whether Zero Trust is a real operating model or just a policy label across human and machine access.

By the numbers:

• 60% of breaches now involve valid credentials, which makes identity the practical decision point for Zero Trust.
• The total of non-human identities outnumbers human identities by as much as 45-to-1, according to CyberArk.
• The average organization expects identities to surge by 3x in the next 12 months.
• 93% of organizations have experienced at least two identity-related breaches.

Context

Identity-first Zero Trust treats identity as the control point for every access decision, whether the subject is a person, service, workload, or application. In this article, CyberArk frames that shift around the fact that valid credentials now let attackers bypass traditional perimeter defences and operate inside trusted sessions.

The governance problem is broader than authentication. The article argues that machine identities, lifecycle controls, privilege controls, and access governance all need to work together if Zero Trust is meant to be continuous rather than episodic. That is the practical issue for IAM and NHI teams: identity has to be governed as an operational control plane, not a compliance exercise.

Key questions

Q: What breaks when Zero Trust is implemented without identity governance?

A: Zero Trust breaks when the policy engine is enforcing stale or incomplete identity data. If access approvals, ownership, and revocation are not governed, the organisation keeps validating entitlements that no longer match business intent. The result is technically strong enforcement built on weak identity records, which still leaves over-privileged accounts and hidden exceptions in place.

Q: When does machine identity risk become a zero trust problem?

A: It becomes a zero trust problem when credentials are persistent, widely reusable, or hard to verify at runtime. Zero Trust depends on continuous validation, but NHIs often operate through automation that assumes trust after initial authentication. Teams should therefore enforce short-lived access and continuous review.

Q: What are the signs that identity controls are not supporting zero trust as intended?

A: Common signs include accounts not using MFA, service accounts being reused for user access, identity stores outside admin control, and assets being accessed through paths that bypass ZTNA or PAM policy. Another warning sign is incomplete visibility into user, service, and device accounts. When those signals appear together, identity governance is not enforcing the intended zero trust boundary.

Q: How should security leaders govern human and machine access together?

A: Use one governance model that covers onboarding, role changes, offboarding, privilege elevation, and certification for both humans and NHIs. Separate workflows create blind spots, but shared identity data and policy enforcement let IAM, PAM, and NHI controls support the same Zero Trust objective.

Technical breakdown

Why valid credentials defeat perimeter-based control

Perimeter models assume the network boundary is the main decision point, but identity-based access changes that logic. If an attacker holds valid credentials, authentication succeeds and the perimeter no longer distinguishes malicious from legitimate access. That is why identity becomes the decision point for Zero Trust. The control challenge is not merely preventing entry. It is continuously re-evaluating trust after entry, across users, services, and machine identities that may already be inside the environment.

Practical implication: move security decisions from the boundary to the identity layer and validate access continuously, not just at login.

Machine identities and the expansion of privileged access

Machine identities are now central because they often authenticate automatically, hold sensitive permissions, and operate at high volume. Unlike human users, they can multiply quickly across applications, pipelines, and services, which makes inventory and lifecycle governance harder. When those identities also carry secrets, API keys, or privileged access, they become a large and durable attack surface. In Zero Trust terms, the question is no longer only who is logging in, but which non-human identity can act with authority and for how long.

Practical implication: inventory machine identities as first-class assets and tie every privileged NHI to ownership, scope, and expiry.

Identity governance as the control plane for zero trust

The article links Zero Trust to three control families: privilege controls, access management, and identity governance. That matters because least privilege, JIT access, ZSP, MFA, adaptive authentication, RBAC, ABAC, and access reviews only work when the underlying identity data is accurate and current. Identity governance is what makes those controls coherent across joiners, movers, leavers, and non-human actors. Without that orchestration, Zero Trust becomes a collection of disconnected controls rather than a dynamic security model.

Practical implication: align identity governance, PAM, and access management so policy decisions remain synchronized across human and machine estates.

Threat narrative

Attacker objective: The objective is to operate through trusted identity paths so the attacker can bypass controls, maintain stealth, and reach data or systems that perimeter defences would otherwise protect.

1. Entry begins when attackers obtain valid credentials or otherwise compromise a trusted identity, allowing them to authenticate without triggering perimeter resistance.
2. Escalation follows when those credentials belong to a privileged human or machine account, giving the attacker broader access than the initial breach would suggest.
3. Impact occurs when the attacker operates through trusted access paths for extended periods, bypassing controls and exposing data or other resources without immediate detection.

Breaches seen in the wild

• Shai Hulud npm malware campaign: Shai Hulud campaign: npm malware exposed secrets on GitHub.
• 230M AWS environment compromise: 230M AWS environments compromised via exposed .env files with cloud credentials.

Read and download The State of NHI & AI Agent Breach Report 2026, covering 200+ breaches impacting Non-Human Identities including AI Agents.

NHI Mgmt Group analysis

Identity is now the control plane, not a supporting control. CyberArk’s core argument is that perimeter logic fails once valid credentials are the dominant access path. That shifts Zero Trust from a network-centred model to an identity-centred operating model across humans, services, and machine identities. The implication is that identity governance now determines whether Zero Trust can be enforced at all.

Machine identity growth is what turns the model from theory into operational risk. Non-human identities outnumber human identities by as much as 45-to-1, and that ratio changes the governance problem materially. Machine credentials scale faster than manual oversight, so lifecycle, privilege, and ownership controls become the limiting factor. This is where NHI governance stops being a niche discipline and becomes the foundation for scalable Zero Trust.

Identity-first Zero Trust only works when privilege is temporal and provable. Least privilege, JIT access, ZSP, and access reviews are not separate initiatives here. They are the mechanisms that prove trust is time-bound and task-bound instead of standing and reusable. If an organisation cannot show who has access, when, and why across humans and NHIs, Zero Trust remains aspirational rather than enforceable.

Structured identity governance is the difference between architecture and posture. The article’s roadmap framing is important because fragmented controls do not create a coherent programme. IAM, PAM, and NHI controls have to be orchestrated as one control plane so access decisions, certification, and escalation handling remain synchronized. Practitioners should treat identity governance as the programme spine, not as a compliance afterthought.

From our research library:

• 90% of IT leaders say properly managing NHIs is essential for a successful zero-trust implementation, according to the Ultimate Guide to NHIs.
• Read next: Zero Trust Identity Guide

What this signals

Identity-first Zero Trust only becomes operational when governance can keep pace with machine identity sprawl. The challenge is not proving that identity matters, because that is already settled. The challenge is making sure access reviews, privilege controls, and lifecycle processes can govern non-human identities at machine speed without turning into a backlog.

Machine identity governance is the missing connective tissue between IAM and Zero Trust. Organisations that keep treating NHIs as sidecar assets will struggle to sustain least privilege, JIT, and continuous verification in practice. For security leaders, the next step is not another policy statement but a control model that treats non-human access as continuously managed infrastructure.

For practitioners

• Map machine identities as critical assets Build an inventory of service accounts, API keys, tokens, certificates, and other non-human identities, then assign ownership and business purpose to each one.
• Tie privileged access to time-bounded issuance Use just-in-time access and zero standing privileges for human and machine administration paths so elevated rights do not persist beyond the task.
• Align identity governance with access enforcement Connect access reviews, RBAC, ABAC, and lifecycle controls to the same authoritative identity data so policy decisions stay current across joiners, movers, and leavers.
• Use continuous verification for trusted sessions Treat successful authentication as the start of trust validation, not the end, and apply adaptive controls when session context changes.
• Define a roadmap for identity control orchestration Sequence privilege, access, and governance controls so the programme can scale without leaving gaps between teams or toolsets.

Key takeaways

• Perimeter security is weaker than identity-based control when valid credentials are already enough to enter an environment.
• Machine identities outnumber human identities at scale, which makes lifecycle and privilege governance a core Zero Trust requirement.
• The practical test for identity-first Zero Trust is whether access can be continuously verified, time-bounded, and consistently reviewed across humans and NHIs.

Key terms

• Identity-first Zero Trust: An access model that treats identity as the primary enforcement point instead of network location. Every request is evaluated using context, entitlements, and risk signals so trust is continuously earned rather than assumed.
• Machine Identity: The digital identity of a machine, device, or workload, such as a server, container, or VM, used to authenticate it within a network. Sometimes used interchangeably with NHI, though NHI is the broader category.
• Continuous Verification: A Zero Trust practice that re-evaluates trust during the session instead of relying on a single successful login. The control is stronger when context signals are available in real time and when the identity programme can act on those signals without creating excessive exceptions.
• Zero Standing Privileges (ZSP): A security posture where no identity, human or non-human, holds persistent access rights. Access is provisioned dynamically on demand and automatically revoked after use. ZSP is the gold standard for NHI access control.

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 building or maturing an IAM programme, it is worth exploring.