Machine identity management (MIM) involves issuing, rotating and revoking the credentials that machines—such as servers, endpoints, network devices, virtual machines and IoT devices—use for authentication and secure communication.
Similar to humans, machines must present credentials to access systems and data. But where humans rely on usernames, passwords and multifactor authentication (MFA), machines rely on device credentials such as keys and certificates.
These credentials allow machines to prove their identity. Common forms include TLS certificates for secure network connections, SSH keys for remote access and public key infrastructure (PKI)-issued device certificates for device authentication.
As machine-to-machine communication grows, securing machine identities against cyberthreats has become a major challenge. According to the IBM X-Force Threat Intelligence Index, identity-based attacks—where cybercriminals abuse valid account credentials to access networks—account for 32% of data breaches.
Modern infrastructures can also make managing machine identities more difficult. IT environments scale rapidly, provision and decommission devices frequently and need to constantly renew credentials.
MIM helps bring order to this complexity and improve cybersecurity. It enables security teams to discover where device credentials live, automate rotation and revocation, enforce security policies and monitor for expiry or misuse.
With MIM, organizations can support zero trust architecture and reduce unauthorized access, data breaches and outages from expired certificates. They can also limit the potential exposure of leaked keys and gather the audit trails necessary for regulatory compliance.
In identity security, nonhuman identities (NHIs) are digital identities assigned to nonhuman “users,” such as apps, services, workloads, containers, APIs, bots and AI agents and devices.
A machine identity is a subset of NHIs specifically associated with a device, such as a server, virtual machine, endpoint, network device or IoT device.
The term machine identity is sometimes used as a loose catchall for any NHI, although this usage is technically incorrect. Machine identity management specifically focuses on managing machine identities and their credentials.
That said, machines frequently interact with software and services that authenticate by using service accounts and credentials such as API keys. MIM programs are often implemented alongside broader nonhuman identity management and governance efforts.
The rise of AI agents is also further blurring the divide between nonhuman and machine identities. AI agents often execute work through workloads and service identities and can even delegate tasks across systems. This means that they are frequently operating at the intersection of both nonhuman identities and machine identities.
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Estimates vary—from 45:1 to 92:1—but in most IT environments, nonhuman identities significantly outnumber humans.
And IT environments continue to evolve, driven by the adoption of cloud infrastructure and software as a service (SaaS), the rise of distributed systems and microservices and the growth of connected devices. With each, the number of machines grows, along with the variety of credentials.
In addition to being numerous, machine credentials are attractive to cybercriminals. Unlike human users, machines often run continuously, authenticate automatically and cannot rely on interactive controls, such as MFA prompts. They’re also often implicitly trusted in networks and workflows, which can increase the impact when credentials are compromised.
Some of the most common security risks associated with machine identities include:
The sheer number of machine identities in a system, and the pace at which new devices and instances are provisioned, can make visibility difficult, creating gaps that cybercriminals can sneak through.
Many organizations also neglect to formally decommission machine identities when decommissioning servers, retiring virtual machine images or removing devices from service. These old identities are often unmonitored, with their permissions intact.
Because they are integral to core workflows, machine identities are often granted privileged access to sensitive data. In the interest of ensuring these processes “just work,” organizations often grant device credentials broader permissions than they need.
Machines might not have passwords, but they do use OAuth tokens, certificates and other secrets to authorize and authenticate themselves. These secrets can be stolen and misused much the same way human users’ passwords can, enabling unauthorized access, lateral movement and privilege escalation.
Devices and device management systems often connect to third-party platforms (for example, IoT fleet management or device monitoring providers). But if credentials from those third-party platforms are compromised, attackers can move laterally across environments.
When servers are decommissioned, virtual machine images are retired or devices are removed from service, old credentials can persist. Without systematic revocation and decommissioning, these orphaned device credentials can become security risks.
Organizations usually manage several types of machine identity credentials, each with distinct characteristics and security requirements.
Machine identity management automates and operationalizes the machine identity lifecycle, managing credentials from issuance to deprovisioning.
Core stages of the machine identity management lifecycle include:
Discovery involves scanning networks, cloud environments, certificate stores and application configurations to identify all device credentials in use, including credentials outside of formal IT systems.
Security teams can frequently find credentials they didn’t even know existed, such as SSH keys on forgotten servers or device certificates embedded in legacy systems.
When a new machine identity is established or identified, MIM entails issuing that identity new credentials. A formal MIM program enables organizations to create credentials through controlled, auditable processes rather than ad hoc, manual handling.
When provisioning—giving the right credentials to the right machines—organizations often try to follow the principle of least privilege, granting each machine only the exact level of access it needs to carry out its functions.
For example, a virtual machine created in the cloud can be assigned a specific identity within an IAM system. MIM can then help ensure that the virtual machine automatically receives the short-lived credentials it needs. These credentials allow it to access only the specific cloud resources it’s meant to use—such as a single storage bucket or a secrets vault—without storing long-term access keys on the machine.
Rotation means replacing credentials periodically or after suspected exposure. It involves issuing new certificates or keys and retiring the old ones.
Credentials have limited lifespans by design. For example, TLS certificates typically expire after 90 days to one year. This limited lifespan serves two purposes.
First, it reduces the window of opportunity for attackers. If credentials are stolen, they become useless when rotated out.
Second, regular rotation helps prevent outages caused by expired certificates, which can take IT teams by surprise.
Automation makes rotation and renewal manageable at scale by eliminating the need for manual tracking. Instead of spreadsheets and calendar reminders, machine identity management platforms can monitor expiration dates through a credential inventory and automatically trigger certificate renewals and key rotations.
When necessary—such as when a certificate is compromised or a device is decommissioned—MIM can revoke certificates immediately. Revocation generally involves adding the certificate to a certificate revocation list or using Online Certificate Status Protocol (OCSP) responders—servers that answer real-time queries about whether a certificate is still valid.
Deprovisioning also involves the regular removal of credentials when devices and infrastructure components are retired. For ephemeral resources that exist for seconds or minutes, MIM helps ensure that deprovisioning occurs automatically when resources are destroyed.
Several technologies and practices form the foundation of MIM. Some of the most significant include:
Public key infrastructure is a comprehensive framework for assigning, identifying and verifying user identities through digital certificates. It is the primary framework many organizations use to issue, manage and revoke digital certificates.
A certificate authority (CA) issues certificates after validating the identity of the requesting entity, such as a server, device or organization. Certificates contain valuable information, such as the requesting entity’s public key and the CA’s digital signature, which help prove the entity’s identity.
For example, when a web server needs a TLS certificate, it submits a request (often in the form of a certificate signing request, or CSR) to a CA. The CA validates the request and issues the certificate. The server can then use the certificate to establish HTTPS connections.
In some PKI deployments, a registration authority (RA) can also approve certificate requests before the CA issues the certificate. RAs can strengthen security by adding an approval step and enforcing separation of duties.
CLM tools automate discovery, tracking, renewal and revocation of certificates. They provide centralized visibility across hybrid environments spanning cloud and on-premises systems. CLM tools can alert administrators to upcoming expirations and trigger automated workflows to renew, rotate and revoke credentials.
For instance, a CLM tool might discover 500 certificates across an organization’s cloud and on-premises environments, flag 30 expiring within 30 days and automatically renew them—preventing outages without manual intervention.
Secrets management solutions can securely store and rotate credentials used by infrastructure automation and device management workflows (for example, SSH keys and other privileged secrets). Secrets management tools enable teams to keep device secrets in a protected vault rather than in a code repository or other unsecured location.
Secrets management tools can often integrate with DevOps workflows to help provision credentials on demand, enforce access policies and maintain audit logs.
Privileged access management (PAM) tools help manage highly privileged credentials. They often provide features such as session monitoring and just-in-time provisioning—granting access only when needed and revoking it automatically afterward.
For instance, rather than giving an engineer permanent root access to production servers, PAM can provision temporary SSH credentials that expire after a maintenance window, reducing standing privilege.
HSMs are tamper-resistant hardware devices for storing private keys. They protect cryptographic material from extraction, even if attackers access the server. HSMs are often valuable for financial services and regulatory compliance.
For example, a bank might store the private keys for its payment processing certificates in an HSM, which helps ensure that the keys cannot be extracted even if cybercriminals breach the application server.
MIM and identity and access management (IAM) are both part of identity security, which focuses on protecting digital identities and the systems that manage them.
The main difference is in what they protect. IAM mainly focuses on human users, while MIM focuses on machines.
IAM systems often use interactive flows—password entry, MFA prompts, biometrics—that assume a person is present, whereas MIM must use automated credential exchange with no human intervention.
Modern identity security programs generally require both IAM and MIM, and most identity governance and administration (IGA) frameworks treat machine identities alongside humans. Machines have similar governance needs as human users. In both cases, organizations must track what exists, what it can access and whether that access remains appropriate over time.
MIM can help organizations strengthen security, maintain uptime and simplify compliance.
MIM provides a unified view of device credentials across an enterprise’s entire ecosystem.
This capability can make it easier for security teams to identify vulnerabilities—orphaned credentials, excessive permissions, certificates near expiration—and fix them before hackers can attack.
Automated policy enforcement can also help IT teams apply security standards consistently, reducing the risk of exploitable misconfigurations.
Expired certificates are a common cause of unexpected downtime. Without a valid certificate, a machine can’t authenticate or establish an encrypted connection, which can cause services to go offline or fail. Automated certificate management can help prevent these disruptions by renewing credentials before they expire.
MIM can help organizations maintain compliance with regulations such as the General Data Protection Regulation (GDPR), Payment Card Industry Data Security Standard (PCI-DSS), Health Insurance Portability and Accountability Act (HIPAA) and Sarbanes-Oxley Act (SOX). MIM documents credential ownership, rotation history and access to sensitive systems, making it easier to provide audit trails and streamlining compliance reviews.
MIM can make scaling IT infrastructure easier, enabling rapid growth in cloud workloads, containers and connected devices without proportional increases in management. It does this by automating credential issuance, rotation and revocation, making it easier for IT teams to keep identities secure as environments grow.
Smooth scaling is increasingly important as organizations expand their ecosystems of microservices, IoT devices and AI agents, with each adding new machine identities and credentials that must be managed across their lifecycle.
Zero trust requires continuous validation of every connection, human or machine. MIM can help make continuous validation practical by discovering and cataloging machine identities—a necessary first step because organizations cannot validate credentials they haven’t identified. It can also support least privilege by automating access controls and applying them consistently across environments.
Despite its many benefits, organizations can face challenges when implementing and operating MIM.
Machine credentials are rarely managed through a single system or security solution. Security teams might use one tool for PKI certificates and another for secrets management, with ops teams maintaining their own credentials entirely. This tool fragmentation can create significant visibility gaps and policy inconsistencies.
Human users generally have managers who periodically approve access requests and review permissions. Machine identities can lack the equivalent oversight. For instance, when the engineer who provisioned credentials changes roles or leaves the organization, accountability can disappear with them. Without explicit ownership, credentials can go unreviewed for years.
MIM depends on automation. But fully automated rotation can break applications and systems that expect static credentials, such as keys embedded in configurations—causing outages when a system suddenly can’t authenticate. Organizations must balance enough automation to achieve their priorities with enough oversight to catch errors before they reach production.