Extending Zero Trust to Machines: The Next Step in Identity-Centric Security

Read full article here: https://corsha.com/blog/why-zero-trust-must-include-machine-identity-management/?utm_source=nhimg

Zero Trust has become the gold standard in modern cybersecurity frameworks. Its core principle — never trust, always verify — reshapes how organizations secure data, users, and workloads. But achieving true Zero Trust, consistently and comprehensively, is harder than it sounds.

According to Gartner, 60% of organizations will adopt Zero Trust architecture by 2025. Yet, more than half of those efforts will fail to deliver the expected security benefits. Why? Because most Zero Trust implementations still focus primarily on human identities — users, employees, administrators — while leaving out a rapidly expanding and equally important category: machine identities.

In today’s environment of continuous automation and API-driven systems, ignoring machine identity management (MIM) leaves a dangerous blind spot. These non-human entities — workloads, containers, microservices, bots, and APIs — now outnumber human identities by a factor of 20 to 1 in large enterprises.
Without managing and verifying these machine identities, Zero Trust simply can’t live up to its name.

Why Machine Identity Management Is Core to Zero Trust

Machine identity management (MIM) is the process of governing, authenticating, and orchestrating non-human identities that enable digital systems to communicate securely. In Zero Trust architecture, every identity — human or machine — must be continuously verified, not just authenticated once.

MIM provides that continuous verification for workloads and APIs, enforcing trust boundaries between automated systems. It ensures that each machine, service, or process making a request is both known and authorized to do so.

This capability is critical for securing API communications, which form the backbone of modern digital ecosystems. Without strong machine identity controls, threat actors can exploit weak API credentials or outdated secrets to impersonate trusted systems — effectively bypassing Zero Trust defenses.

Static Credentials Are Obsolete

Relying on static, long-lived keys, certificates, or secrets is no longer enough.

Gartner predicted that APIs would become the most common attack vector by 2022 — and that prediction has proven true. Hard-coded credentials, unrotated secrets, and orphaned machine certificates are fueling an ongoing wave of breaches.

According to Ponemon Institute:

• 53% of organizations don’t know how many active keys or certificates they have.
• Over 60% admit to inconsistent credential rotation.

When a single API key leaks — whether from a GitHub repository, a misconfigured service, or a third-party integration — attackers gain immediate and often unlimited access.

In 2022, security researchers discovered over 3,200 mobile apps leaking Twitter API keys, many with full read/write permissions. Such incidents show that secrets hygiene alone can’t meet Zero Trust standards. You can’t "trust" a secret — only verify it dynamically.

The Rise of Machine Identity Management

The exponential growth of connected devices is accelerating this problem. Cisco predicts that over 29 billion devices will be connected to the internet by 2023. Most of that traffic is machine-to-machine (M2M) — not human.

Automation has improved efficiency, but it has also multiplied attack surfaces. Machines create, deploy, and retire faster than traditional identity systems can track. Without centralized visibility and lifecycle management, orphaned identities become silent backdoors for adversaries.

This is where Machine Identity Management enters as a key pillar of Zero Trust — bringing automation, rotation, and verification to machine credentials the same way Identity Governance and Access Management (IGA) do for humans.

Defining Machine Identity Management

Machine Identity Management (MIM) governs how machines prove their identity within digital ecosystems. It includes:

• Certificate lifecycle automation (creation, rotation, revocation)
• Key and secret governance
• API identity verification
• Policy-driven access control for workloads
• Integration with PKI and Zero Trust frameworks

A robust MIM program ensures that every API, container, and microservice uses a dynamic, short-lived, and verifiable credential. It goes beyond static authentication to establish continuous assurance — the foundation of any real Zero Trust implementation.

Key Strategies for Strengthening Machine Identity Management

1. Assess Your API Security Scorecard

Start by evaluating your organization’s API posture. Frameworks like NIST SP 800-207 and the CISA Zero Trust Maturity Model can serve as scorecards for assessing:

• Credential management practices
• Authentication enforcement mechanisms
• Authorization boundaries for machine-to-machine interactions

This helps identify weaknesses such as untracked service accounts, unrotated secrets, or APIs lacking fine-grained access controls.

2. Automate Identity Lifecycle Management

Manual credential rotation is not sustainable at scale. Organizations must deploy automated MIM platforms that handle the full lifecycle of keys, certificates, and tokens — from issuance to expiration.

Automation ensures continuous enforcement of Zero Trust principles and eliminates the human error behind delayed rotations or expired credentials.

3. Implement Multi-Factor Authentication (MFA) for Machines

Human users have long benefited from MFA. Now, it’s time to apply the same concept to machines.

MFA for machines ensures that even if a credential is stolen, the attacker cannot authenticate without the required secondary proof — such as a time-based token, workload attestation, or dynamic cryptographic challenge.

This machine MFA establishes a “story” for each non-person entity (NPE), documenting who, what, when, and where behind every API request. That visibility is vital for forensic investigations and continuous trust evaluation.

4. Monitor and Continuously Verify

Zero Trust is not a one-time check — it’s an ongoing process. Deploy behavior analytics to detect anomalies such as:

• API clients accessing unusual endpoints
• Service accounts authenticating from new geolocations
• Unexpected certificate reissuance or renewal patterns

Integrating continuous verification closes the gap between compromise and detection, reducing the window of exploitation.

Real-World Lessons: Why MIM Matters

The 2022 URLScan data exposure incident revealed the risks of relying solely on secrets management. The service accidentally leaked API keys and tokens publicly — including those belonging to major security vendors. This illustrates how even well-intentioned automation can fail if identity verification isn’t automated end-to-end.

Similarly, when third-party integrations lack proper MIM, their weaknesses become your weaknesses. Zero Trust assumes no inherent trust — not even in vendors. Automated machine identity management helps enforce that boundary.

Staying True to Zero Trust

Zero Trust’s most important principle is continuous verification. To uphold that principle across APIs and automation, machine identities must be treated with the same rigor as human identities.

A mature Zero Trust program:

• Dynamically authenticates both users and machines
• Continuously validates every connection and transaction
• Adapts in real time based on behavior, context, and policy

Without Machine Identity Management, Zero Trust remains incomplete — a partially built wall around a continuously evolving perimeter.

Conclusion

Machine Identity Management is no longer optional. It’s a foundational enabler of Zero Trust — ensuring every machine, service, and API request is verified, authorized, and monitored.

By embracing automated MIM, implementing MFA for machines, and aligning with frameworks like NIST 800-207, organizations can transform Zero Trust from a static concept into a living, adaptive security architecture.

If you’re building or modernizing your Zero Trust strategy, start by asking:

“Do we truly know which machines we trust — and why?”