- Non-human identities outnumber human user accounts by 10x to 50x in most enterprise environments.
- NHI security failures, including long-lived secrets, excessive privileges and orphaned accounts, significantly increase cloud security risk.
- Security teams managing NHI environments should prioritize lifecycle governance, credential rotation and least-privilege access controls.
What Is NHI?
A non-human identity (NHI) is any digital credential or identity record that belongs to a system rather than a person.
While a human identity is tied to a user account protected by a password or biometric, an NHI belongs to software, such as a microservice calling an API, a CI/CD pipeline or an AI agent performing automated tasks.
NHIs authenticate using programmatic credentials like API keys, JSON Web Tokens (JWTs), OAuth tokens, X.509 certificates, SSH keys, and cloud identity and access management (IAM) roles.
The term overlaps with “machine identity,” and many practitioners use the two interchangeably.
But machine identity traditionally refers to device-level certificates, while NHI covers any non-human principal, including service accounts, workload identities, bots and agentic AI systems.
In other words, all machine identities are non-human identities, but not all non-human identities (such as AI agents) are physical machines.
Types of Non-Human Identities
Non-human identities take several forms, each suited to a different authentication scenario.
| NHI Type | Credential Form | Typical Use Case |
|---|---|---|
| Service Account | Username/password or Kerberos ticket | Application-to-database or app-to-app access in Windows/Active Directory environments |
| API Key | Static string secret | Third-party SaaS integrations and developer tool access |
| OAuth Token / JWT | Short- or long-lived bearer token | Delegated authorization between web apps and APIs |
| Cloud IAM Role | Assumed role with temporary credentials | AWS, Azure, and GCP workload access to cloud resources |
| X.509 Certificate | Public/private key pair | Mutual TLS (mTLS) between services and device authentication |
| SSH Key | Key pair | Automated server access in DevOps pipelines |
| AI Agent Identity | Token, certificate, or IAM role | Agentic AI systems authenticating to tools and data sources |
Why NHI Security Matters
NHIs are one of the fastest-growing attack surfaces in enterprise security.
A 2024 survey of 818 professionals by the Cloud Security Alliance found only 15% feel highly confident preventing NHI attacks, while 69% express concern about their NHI exposure.
Several structural factors make non-human identities uniquely difficult to protect:
- No MFA fallback: NHIs cannot use biometric or push multi-factor authentication (MFA). A leaked API key is immediately usable by anyone who holds it.
- Long-lived credentials: API keys and service account passwords often lack expiration dates, turning one leaked secret into a persistent backdoor.
- Identity sprawl: NHIs multiply across cloud, CI/CD and third-party integrations. The same CSA survey found just 20% of organizations have formal processes for offboarding and revoking API keys.
- Weak visibility: Identity governance tools are built around human user directories. NHIs often exist outside those systems, leaving teams with no inventory, owner or audit trail.
Once an attacker holds a service account credential or IAM role, they can move laterally without triggering human-centric detection controls.
Non-Human Identity Management
Non-human identity management (NHIM) governs NHI access across its full lifecycle. Key practices include:
- Discover and inventory: Catalog every NHI, its owner, its permissions and where its credentials are stored. You can’t secure what you can’t see.
- Apply least privilege: Each NHI should hold only the permissions its current function needs, nothing broader.
- Rotate credentials: Replace secrets, tokens and certificates on a schedule. Short-lived credentials shrink the exposure window if a secret leaks.
- Monitor for anomalies: Log NHI activity and flag deviations, such as unusual API call volumes or unexpected access.
- Decommission promptly: Orphaned NHIs are low-effort targets. When a service is retired or an integration removed, revoke its access and deactivate the identity immediately.
The OWASP Non-Human Identities Top 10 (2025) names improper offboarding (NHI1), secret leakage (NHI2), and overprivileged NHIs (NHI5) among the top-ranked risks, making it a practical checklist for any NHIM program.
But don’t jump ahead — start with step 1 (inventory) first.
The Wrong NHI Type Will Compromise Your Security
Since many NHI types are vulnerable to misuse, always choose the most secure NHI type for your use case. For example, bad actors can copy API keys from config files and use them from anywhere.
But hardware-bound key pairs, such as those assigned to a device with an X.509 digital certificate, can’t be repurposed on other devices.
What’s more, organizations managing NHIs should immediately adopt post-quantum encryption standards recommended by the National Institute of Standards and Technology (NIST).
With these algorithms, even vulnerable NHIs can withstand increasingly advanced attacks.
This might sound complicated, but it doesn’t have to be. Many NHIM solutions already prioritize automated IAM with post-quantum cryptographic standards, which removes the guesswork from NHI tech.
Related Terms
Frequently Asked Questions
What is NHI in cybersecurity?
NHI stands for non-human identity: any digital identity assigned to a machine, application, service account or automated process, not a person.
How do non-human identities differ from machine identities?
Machine identity is a narrower term focused on device-level certificates and keys, while non-human identity also includes service accounts, API keys, OAuth tokens, cloud IAM roles and AI agent credentials.
What credentials do non-human identities use?
NHIs authenticate using programmatic credentials such as API keys, OAuth tokens, JWTs, X.509 certificates, SSH keys and cloud IAM role tokens.
Why are non-human identities difficult to secure?
NHIs cannot use MFA, often lack expiration dates, proliferate faster than teams can track them, and exist outside traditional human-centric identity governance tools.
What is the OWASP NHI Top 10?
The OWASP Non-Human Identities Top 10 (2025) is a community-maintained list of the highest-severity NHI risks, covering improper offboarding, secret leakage, overprivileged identities and long-lived credentials.
Securing AI agents and workloads?
SecureW2 issues short-lived, certificate-based identities to non-human and agent identities so every connection is authenticated. See how it maps to your stack.