Why do service account tokens increase lateral movement risk?

Why This Matters for Security Teams

service account tokens are risky because they turn a machine action into a reusable identity artifact. Once a token is copied, logged, shared in a ticket, or left active after the original job finishes, an attacker can pivot with the same authority as the workload itself. That is why token exposure is so often a lateral movement problem, not just a secrets hygiene problem. NHIMG research on the 2025 State of NHIs and Secrets in Cybersecurity found that 44% of NHI tokens are exposed in the wild, which helps explain how quickly one compromised token can become multiple internal footholds.

The mistake many teams make is treating service accounts as plumbing instead of governed identities. Under NIST Cybersecurity Framework 2.0, identity and access management should be tied to asset criticality, lifecycle control, and monitoring, but service account tokens often sit outside those processes. That gap is why a token stolen from a build pipeline, admin console, or chat thread can be reused across systems that were never meant to share trust. In practice, many security teams encounter lateral movement only after an exposed token has already been used to enumerate systems and expand access.

How It Works in Practice

A service account token increases lateral movement risk when it is valid across more than one system, has a long lifetime, or is stored in places that are easy to copy from. The attacker does not need to break authentication if the token already proves identity. They only need to find where it was issued, where it still works, and whether the permissions attached to it can reach other apps, APIs, or cloud resources. That is why token scope and token lifetime matter as much as the secret value itself.

Best practice is evolving toward tighter workload identity, JIT credentials, and explicit revocation. A service account should be treated as a workload identity with a clear owner, a narrow role, and a measurable purpose. Where possible, short-lived credentials should replace static tokens so access expires automatically after the task ends. Policy checks should happen at request time, not only at onboarding, because static RBAC alone cannot capture the context of what a workload is trying to do. That is especially important in environments where tokens are moved through CI/CD, chat tools, or ticketing systems, which is exactly the pattern seen in the Guide to the Secret Sprawl Challenge and in incident patterns like the Salesloft OAuth token breach.

• Issue tokens for one workload and one purpose, not for broad reuse across teams.
• Set short TTLs and automate revocation when the job, deployment, or approval window closes.
• Store tokens in a vault or broker, not in code, tickets, or long-lived config files.
• Monitor token use for unusual source systems, times, and access paths that suggest reuse.
• Review whether the token can reach other identities, clusters, or tenants that should be isolated.

These controls tend to break down in legacy automation estates where the same token is embedded in scripts, shared runners, and unmanaged integrations because revocation then becomes a coordinated outage risk.

Common Variations and Edge Cases

Tighter token controls often increase operational overhead, requiring organisations to balance reduced lateral movement risk against deployment speed and automation stability. That tradeoff is real in environments that rely on shared service accounts, brittle pipelines, or vendor integrations that cannot yet support per-task credentials. Current guidance suggests isolating those exceptions instead of normalising them across the estate.

There is no universal standard for every environment, but the direction is clear: tokens that never expire, are reused by multiple apps, or survive offboarding are the highest-risk pattern. The 2025 State of NHIs and Secrets in Cybersecurity reported that 91% of former employee tokens remain active after offboarding, which shows how lifecycle failure compounds lateral movement risk long after the original user or task is gone. In addition, the Dropbox Sign breach and the JetBrains GitHub plugin token exposure illustrate how a single exposed credential can become broad internal access when governance is too thin.

For teams aligning to NIST Cybersecurity Framework 2.0, the practical move is to classify service account tokens by exposure path and reissue them under least privilege, rather than waiting for a full identity redesign. In some regulated or high-availability systems, long-lived tokens may persist temporarily, but they should be wrapped with compensating controls such as vaulting, network segmentation, and continuous anomaly detection.

Related resources from NHI Mgmt Group

• Why do service accounts and AI agents increase lateral movement risk?
• How should teams respond when a service account token is exposed?
• Why do SSO environments increase the risk of lateral movement?
• Why does unconstrained delegation increase the risk of lateral movement?