Securing Non-Human Identities: Why It Matters and How to Get It Right

A non-human identity refers to any identity used by a machine rather than a human. For example:

• Devices: servers, laptops, mobile devices
  
• Workloads: containers, virtual machines, applications, microservices
  
• AI agents
  

Common types of NHIs include secrets, keys, and certificates: 

• API keys 
• Tokens (OAuth, JWT, etc.) 
• Passwords 
• Accounts (service, cloud, system, app) 
• Encryption keys 
• SSH keys 
• X.509 certificates (TLS, Client, SPIFFE, etc.)
  

Some vendors use the term “machine identity” instead of NHI. For all practical purposes, the terms are interchangeable, though “NHI” typically emphasizes workload identity management over physical devices.

For every employee in your organization, there may be dozens or even hundreds of non-human identities. The average enterprise now manages thousands of containers, microservices, and applications, each with its own credentials. Yet while human identities are subject to strong oversight, NHIs often operate in the background — unmanaged, untracked, and unsecured.

This creates significant security risks:

Lack of visibility

NHIs are created by different teams using different tools, resulting in a scattered identity landscape. Many organizations don’t know how many NHIs they have, where they’re located, or what they access.

No governance

There’s often no centralized policy governing how NHIs are issued, renewed, or revoked. Credentials may be hardcoded into scripts, stored in plain text, or simply forgotten after deployment.

Manual and fragmented processes

Inconsistent tooling and decentralized workflows make generating, rotating, or retiring machine credentials slow and error-prone, resulting in shadow IT and unmonitored access paths.

Attack surface expansion

Unmanaged or expired NHIs are a prime target for attackers. Compromising an NHI can give unauthorized access to critical systems, data pipelines, or cloud infrastructure.

NHIs power everything from automated DevOps pipelines to intelligent IoT devices. Some examples include:

• A CI/CD pipeline using an OAuth token to deploy code to Kubernetes
• An IoT device using a TLS certificate to securely send telemetry data
• A serverless function calling an API using a static API key
• A cloud VM authenticating to storage with a service account
• A machine-learning model using SSH to access a secure training environment
  

In all these cases, an identity is used without any human interaction, and unless that identity is properly managed, it introduces risk.

IT and security teams are used to managing human users — employees, partners, and customers. These identities have long lifespans and are tied to real-world people and roles. NHIs, by contrast, may be:

• Ephemeral: A microservice that exists for 30 seconds
• Hard to track: Credentials issued by automated scripts
• Ambiguous: Is a hardcoded API key an identity or just a credential?
  

The lifespan of NHIs varies wildly — some expire in minutes, others persist for years (or forever). That variability makes it difficult to apply standard identity practices.

Let’s be honest: “Non-Human Identity” is a trendy term, and some vendors use it more to ride the hype than to drive innovation. But the shift from “machine identity” to “non-human identity” does highlight an important point:

Identity was never just about people.

As our digital ecosystems evolve, so must our understanding of identity. NHIs help remind us that automated processes, digital agents, and connected devices also need secure, verifiable identities — and that traditional IAM tools aren’t always built to support them.

Among the many credential types used for NHIs, X.509 digital certificates issued through PKI stand apart. They provide:

• Strong authentication via cryptographic key pairs
• Encrypted communication to protect data in transit
• Verifiable identity tied to policies and lifecycle controls
  

Unlike tokens or passwords, certificates are non-reusable, tamper-evident, and cryptographically secure — making them ideal for securing NHIs in zero trust architectures.

At Keyfactor, we believe that PKI is not just another NHI — it’s critical infrastructure. It forms the root of trust that enables secure machine-to-machine communication at scale.

Despite its strengths, PKI isn’t easy to manage without the right tools and partners. Many organizations struggle with:

• Lack of inventory: Not knowing what certificates they have
• Manual renewal: Leading to outages and expired certs
• No policy enforcement: Making it hard to control key sizes, validity periods, or issuance processes
• Tool sprawl: Using homegrown scripts, spreadsheets, or misaligned CA systems

In a world where microservices may request certificates every few minutes, manual processes simply don’t scale.

Every machine — whether it’s a workload, device, or service — has an identity. When those identities are unmanaged or misconfigured, the risks are real: outages, breaches, compliance failures. These stories show how organizations brought order to NHI chaos..

• Global Bank: Eliminating Downtime from Unmanaged TLS Certificates
  TLS certificates are one of the most common types of non-human identities – and one of the most overlooked. A multinational bank had over a million certificates across hybrid infrastructure, many of them manually tracked (or forgotten). After multiple service outages caused by expired machine identities, they chose to automate certificate issuance, renewal, and revocation. The result: 90% fewer manual tasks and zero critical outages – all by treating machine identities as first-class citizens in their security program.
  

• MedTech Leader: Building Trust into Connected Devices
  Each connected medical device this manufacturer shipped acted as a non-human identity on the network, requiring secure, unique authentication. Their certificate provisioning was slow, error-prone, and hard to scale – putting patient data and compliance at risk. They embedded X.509 certificates during production, enabling automated, secure onboarding of each device. NHIs were no longer a compliance gap but a source of competitive trust.
  

• Energy Provider: Securing Machine Identities in OT Environments
  Operational Technology (OT) environments are rich with NHIs – sensors, controllers, and SCADA systems that communicate continuously. But a major utility company discovered their legacy PKI couldn’t scale to these systems, leaving them vulnerable. Thanks to modernizing their PKI infrastructure, they gained visibility into every device identity and automating certificate management for OT endpoints. This transformation reduced the risk of supply chain compromise and made NHI security actionable in critical infrastructure.
  

• SaaS Innovator: Enabling Trusted DevOps with Secure Workload Identities
  In this cloud-native software company, build servers, containers, and automation scripts each relied on their own non-human identities to sign code and access services. Security policies around certificate issuance were slowing down the DevOps team, creating friction. When the team enabled automatic code-signing and workload identity issuance, it ensure that every artifact and process could be trusted, without slowing innovation.

Each of the organizations mentioned above faced a common truth: non-human identities outnumber human ones, and managing them manually is unsustainable. Keyfactor helps companies in all industries turn reactive processes into proactive security – making NHIs visible, auditable, and secure by design.

With Keyfactor, your organization can embed digital trust into their identity fabric by securing the credentials that machines rely on to communicate and authenticate, with PKI as the foundation. Here’s how:

• Establish a strong root of trust with enterprise-grade PKI built for today’s evolving cryptography and machine identity use cases, including support for post-quantum cryptography.
• Map identities to business needs by aligning certificate issuance and access controls to the specific requirements of each workload, system, and environment.
• Automate the full certificate lifecycle — from issuance and renewal to revocation — to eliminate outages, reduce manual effort, and ensure continuous trust.
• Enforce consistent policies and governance across all environments with granular controls, auditing, and workflow approvals.
• Integrate flexibly across your tech stack with deployment options and APIs that support hybrid, cloud, or multi-cloud architectures — without vendor lock-in.
  

Unlike “all-in-one” vendors that force you into their ecosystem, Keyfactor prioritizes flexibility and interoperability, giving you the freedom to secure NHIs within your broader identity strategy.

Here’s how we stack up:

The world of identity has changed. Non-human identities are everywhere, and they’re growing fast. If your organization isn’t managing them with the same rigor as human identities, you’re leaving yourself open to outages, breaches, and compliance failures.

With PKI at the core and modern automation layered on top, you can tame the chaos of NHI sprawl and build a scalable, secure, and resilient identity infrastructure.