Non-human identity attacks are reshaping supply chain security

At a glance

What this is: This article argues that software supply chain attacks increasingly hinge on abused non-human identities such as service accounts, tokens and secrets, not just human account compromise.

Why it matters: IAM, IGA and PAM teams need to treat machine credentials as first-class governance objects because human-centric controls do not cover the access paths attackers now exploit across CI/CD and third-party integrations.

Context

A supply chain attack is an intrusion path that uses trusted build, deployment or integration relationships to reach software, data or infrastructure. In this article, the governance gap is that human identity controls are being applied to machine credentials that operate across CI/CD and third-party connections.

The primary identity problem is not authentication in the abstract, but ownership, scope and monitoring of non-human identities such as service accounts, API tokens, SAS keys and OAuth grants. Those credentials often have broader persistence and reach than human sessions, so compromise can travel quietly through connected environments.

The article’s examples show a typical enterprise pattern rather than an edge case. Once non-human access is embedded in delivery pipelines and vendor integrations, the attack surface becomes continuous and difficult to audit with human-focused IAM alone.

Key questions

Q: What breaks when non-human identities are not governed in software supply chains?

A: When non-human identities are not governed, attackers can use tokens, service accounts, and secrets to reach build, release, and data systems that were never meant to be exposed together. The result is hidden persistent access, broad blast radius, and compromise that can spread through trusted automation before anyone notices.

Q: Why do service accounts and tokens create more supply chain risk than human logins?

A: Service accounts and tokens are often long-lived, reusable, and embedded in automation, which means they can be copied and replayed without interactive challenge. Human login controls like MFA and SSO help with employee access, but they do not by themselves govern machine-to-machine trust or third-party delegated access.

Q: How do security teams know if machine identity governance is working?

A: Look for fewer standing accounts, faster onboarding of automation workflows, auditable role approvals, and visible retention of access records after logout. If teams still depend on manual tracking to explain machine access, governance is only partially effective. Working machine identity governance should reduce both operational overhead and review friction.

Q: What should teams do when a third-party NHI is no longer needed?

A: Revoke the credential, remove any linked permissions, and confirm that the identity cannot still reach build, support or deployment systems. If the offboarding step is skipped, the relationship may end on paper while the access path remains active in practice.

Technical breakdown

Why supply chain attacks now target non-human identities

Software supply chain attacks work by abusing trusted relationships inside development, build and deployment workflows. Non-human identities are central to those workflows because they authenticate automation, repository actions, package publishing, CI jobs and cloud operations. When those identities are weakly governed, an attacker does not need to break the chain at the perimeter. They can borrow the chain’s own trust to modify code, pull data or impersonate an approved process. That makes credentials such as service accounts, tokens and secrets the practical control point, not just the supporting mechanism.

Practical implication: Map every build and deployment workflow to the NHI that authorises it, then treat each credential as a separately governed trust boundary.

How broad permissions turn a stolen token into supply chain reach

A stolen token becomes dangerous when it is not tightly scoped, rotated or isolated to a single purpose. In supply chain environments, a single credential may unlock repository access, CI automation, support systems or cloud storage, which means one compromise can cascade across multiple systems. The technical issue is privilege concentration: automation is efficient because it reuses credentials across tasks, but that reuse also expands blast radius. The article’s cases show that the compromise is often not the identity type itself, but the amount of lateral trust packed into it.

Practical implication: Reduce cross-system scope for each token or service account so compromise cannot automatically propagate across the delivery chain.

Why third-party non-human access is hard to see and harder to govern

Third-party integrations often rely on credentials that sit outside normal employee lifecycles, yet still connect directly to sensitive systems. That creates visibility gaps in inventory, ownership, and offboarding. Traditional IAM and TPRM processes were built around people, contracts and periodic review cycles, but non-human credentials can be created quickly, duplicated invisibly and left active long after the business need changes. Without continuous discovery and metadata enrichment, teams cannot tell which machine identities are legitimate, which are stale and which are overprivileged.

Practical implication: Establish continuous inventory and offboarding controls for third-party NHIs instead of relying on human-oriented review cycles.

Threat narrative

Attacker objective: The objective is to exploit trusted machine access to reach code, secrets, customer data or deployment systems while bypassing human-facing controls.

1. Entry occurs through a compromised or misused non-human identity such as a service account, access token or OAuth grant embedded in a trusted workflow.
2. Credential abuse follows when the attacker uses that identity’s existing permissions to access repositories, support systems, build pipelines or cloud storage.
3. Escalation happens as broad or reused privileges let the attacker move from one automation path into adjacent systems and sensitive assets.
4. Impact is achieved when code, data or deployment trust is altered at scale, often without immediate detection because the activity looks like legitimate automation.

Breaches seen in the wild

• LiteLLM PyPI package breach: LiteLLM PyPI supply chain attack, credentials stolen from users.
• reviewdog Action compromise 2025: A stolen maintainer token poisoned reviewdog/action-setup, leaking CI secrets including the tj-actions bot token used in the next attack.

Read our 52 NHI Breaches Analysis report for a comprehensive view of breaches impacting Non-Human Identities including AI Agents.

NHI Mgmt Group analysis

Supply chain security now depends on NHI governance, not just human IAM. Human MFA and SSO reduce account takeover, but they do not govern service accounts, tokens, SAS keys or delegated app grants that power delivery pipelines and vendor integrations. That shifts the control problem from login protection to machine credential lifecycle, scope and monitoring. Practitioners should treat NHI inventory and governance as part of supply chain resilience, not as a separate hygiene task.

Least privilege fails when machine credentials are reused across trust domains. The article’s incidents show the same pattern: a credential created for one automation purpose is able to reach repositories, support tooling, cloud storage or email systems. That is not just excessive access, it is trust inheritance across systems that were never meant to share a security boundary. The implication is that identity programmes must break credential reuse chains before attackers do.

Third-party NHI access creates trust debt that traditional TPRM does not repay. A vendor relationship may end, but its tokens, service accounts and app permissions often keep working. That is a governance failure, not just an inventory problem, because accountability outlives access unless offboarding is explicit and continuous. Practitioners need to govern non-human access with the same lifecycle discipline applied to high-risk human and privileged accounts.

Ephemeral access in supply chain workflows creates identity blast radius. When a single machine identity can move from code commit to build execution to deployment or support access, the resulting blast radius is determined by credential scope, not by the size of the human team behind it. This is where NHI-05 and NHI-07 become operational risks, because long-lived or overprivileged secrets extend compromise beyond the initial entry point. The lesson is to measure access reach, not just authentication strength.

Non-human identity attacks are a governance problem disguised as an operational convenience problem. Automation made cloud delivery faster, but it also normalised broad, persistent, hard-to-audit credentials. That combination is why supply chain attackers keep returning to machine identities: the controls are fragmented, the ownership is unclear, and the attack path is quiet. Practitioners should expect NHI governance to become a core supply chain control domain, not a niche specialty.

From our research library:

• 92% of organisations expose NHIs to third parties, raising concerns about supply chain security, according to the Ultimate Guide to NHIs.
• Read next: Ultimate Guide to NHIs — Key Challenges and Risks

What this signals

Supply chain governance now has to include machine identities as a first-order asset class. IAM, PAM and TPRM processes that stop at human accounts will continue to miss the access paths that matter most in build and deployment ecosystems. The practical shift is to govern issuance, scope, rotation and revocation for NHIs as part of the same control plane that handles privileged human access.

Third-party NHI visibility is the new boundary problem. According to the Ultimate Guide to NHIs, 92% of organisations expose NHIs to third parties, which means the majority of supply chain relationships now depend on credentials that are often outside employee-centric oversight. Practitioners should expect vendor access reviews to fail unless they include machine ownership, purpose and expiry.

Identity blast radius is the concept teams should use when they assess supply chain exposure. The question is no longer whether a credential authenticates, but how far that credential can travel before it is detected or revoked. That lens helps security leaders prioritise the workflows where a single token can affect code, storage, support systems and production deployment at once.

For practitioners

• Inventory every production NHI Build a live inventory of service accounts, tokens, secrets, SAS keys and OAuth grants across build, support and deployment paths. Include owner, purpose, scope, expiry and revocation path so third-party access can be traced quickly.
• Restrict credential reuse across workflows Assign one machine credential to one workflow or trust domain wherever possible. Avoid shared tokens across repositories, CI jobs and vendor integrations because reuse is what turns a single leak into supply chain reach.
• Rotate and revoke on lifecycle change Trigger credential rotation and revocation when a vendor relationship changes, an employee leaves a team, or a pipeline is retired. Offboarding must apply to non-human identities with the same urgency as privileged human access.
• Monitor abnormal machine identity behavior Alert on unusual token use, unexpected repository reads, off-hours automation and access from new locations or workflows. Behaviour monitoring should focus on the systems that should never be touched by a given credential.
• Reduce secret exposure in code and CI Scan repositories, build scripts and logs for hard-coded secrets and credentials. Treat exposed machine identities as immediate incident candidates because supply chain compromise often starts with visible or reusable secrets.

Key takeaways

• Non-human identities have become a primary supply chain attack path because they carry the machine-to-machine trust that modern delivery pipelines depend on.
• The article’s examples show how service accounts, tokens and OAuth grants can turn one compromise into broad access across repositories, support tooling and cloud environments.
• Security teams need lifecycle governance, scope reduction and continuous visibility for machine credentials if they want supply chain controls to keep pace with attack patterns.

Key terms

• Non-Human Identity (NHI): A digital identity assigned to a non-human entity such as a software application, service account, API key, bot, machine, or AI agent that enables it to authenticate and interact with systems without direct human involvement. NHIs now outnumber human identities in most enterprises by 25 to 50 times.
• Supply chain attack path: A supply chain attack path is any route by which a trusted external tool, dependency or partner becomes the mechanism for compromise. It matters because attackers often abuse legitimate integrations instead of exploiting the core system directly, which makes detection and containment harder.
• Secrets Leakage: Secrets leakage is the exposure of credentials such as API keys, tokens, or certificates in places where they can be discovered and reused. The risk is not just disclosure, but unauthorized authentication that turns a coding or pipeline mistake into active access.
• Identity Blast Radius: The amount of damage a compromised identity can cause across systems, data, and infrastructure. In NHI environments, it is shaped by permissions, network reach, and administrative capability rather than by the credential alone. Reducing blast radius is a containment strategy that limits lateral movement and data exposure.

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.