Look at what the final archive contains, not just what the repository contains. Dry-run packaging, artifact unpacking, and file-path searches will reveal whether local identity files such as .claude/settings.local.json are being selected for release. If the file appears in the artifact, the pipeline is already exposing it.
How to prove the pipeline is exposing a local secret file
The fastest way to verify exposure is to inspect the packaged artifact itself, because the repository tree and the release output can differ. A dry-run packaging step, followed by archive unpacking and path searches, shows whether a local file such as .claude/settings.local.json is being swept into release material.
That matters because build systems often include files through broad include patterns, implicit workspace capture, or reused packaging manifests. If the artifact contains the file, the pipeline is already handling secret-bearing material as deployable output, even if the repository reviewer never intended that path to ship.
When the test is run correctly, the question is not whether the file exists in source control but whether the final bundle, image, or package can reproduce it. That distinction is what separates harmless repository clutter from an actual release-time exposure.
What signals make the exposure obvious?
The clearest signal is a path match inside the final archive or image layer contents. If the file name appears in the shipped artifact, you have proof of inclusion, not just suspicion. Artifact listing, recursive unpacking, and manifest inspection are the practical checks that turn a vague concern into a concrete finding.
Secondary signals include unexpectedly broad file globs, packaging commands that pull in entire working directories, and build steps that preserve dotfiles or local configuration files. These are especially important when the file name suggests environment-specific settings or developer tooling, because such files are often present only on the build host but still get captured by default.
For teams that want a baseline reference on why secret sprawl and secret leakage matter during delivery, the Guide to the Secret Sprawl Challenge covers the broader pattern of hardcoded credentials, CI/CD exposure, and remediation.
What should teams change in the build process?
Build validation should happen at the artifact boundary, not only at the repository boundary. Teams should check what is actually being packaged, then narrow include rules so local-only files, developer settings, and secret-bearing paths are excluded by default unless there is a deliberate release need.
A second control is to make packaging deterministic and inspectable. Dry-run modes, artifact manifests, and unpack-and-compare checks give a repeatable way to confirm that the release output matches the intended file set. That is more reliable than assuming a .gitignore, local convention, or developer discipline will prevent leakage.
When the file is a secret-bearing local configuration, rotation and replacement are usually safer than trying to preserve it in place. NHIMG’s Secrets Management Guide is a useful companion for teams deciding when to move from ad hoc file-based handling to centralised, short-lived, and better-scoped secret delivery.
Risk and Threat Considerations
Local secret files are risky because they are often created for convenience, then accidentally picked up by packaging defaults, container builds, or release scripts. Once they are in the artifact, they can be copied, cached, mirrored, or published far beyond the original machine, which turns a local mistake into a distribution problem.
Failure mechanism: Over-broad packaging rules, recursive directory capture, or unsafe build contexts include developer-local files in release outputs, allowing secrets to leave the workstation and enter the deployable artifact.
Impact: The exposed file can disclose credentials, tokens, or configuration that enables downstream access, environment pivoting, or further secret discovery, especially if the artifact is shared internally or publicly.
Standards & Framework Alignment
This section maps relevant standards and security frameworks to the operational risks and controls described in this guidance.
OWASP Non-Human Identity Top 10 addresses the attack and risk surface, while CIS Controls v8, NIST SP 800-53 Rev 5 and SLSA set the governance and control requirements practitioners need to meet.
| Framework | Control / Reference | Relevance |
|---|---|---|
| OWASP Non-Human Identity Top 10 | NHI-02 — Secret Leakage | The question is about build artifacts exposing secret files. |
| Recommendation — Exclude secret-bearing local files from release outputs and validate the packaged artifact before publishing. | ||
| CIS Controls v8 | CIS-3 — Data Protection | Packaging secret files creates direct exposure of sensitive data. |
| Recommendation — Restrict sensitive file inclusion in builds and verify release artifacts before distribution. | ||
| NIST SP 800-53 Rev 5 | CM-5 — Access Restrictions for Change | Build pipelines need controls that prevent unauthorized release-time inclusion of local secret material. |
| Recommendation — Apply release-change controls to stop unintended files from entering deployable artifacts. | ||
| SLSA | Supply-chain integrity | The issue is build-time artifact integrity and provenance of what gets shipped. |
| Recommendation — Verify artifact contents and provenance so build outputs cannot smuggle unintended files. | ||
Practitioner Guidance
What to verify: Confirm the exact file list inside the final artifact, not just the repository, and repeat the check for every packaging path your release process uses. If the file appears in any output form, treat that as a release-control failure, not a documentation issue.
Common mistake: Teams often rely on source-control ignores or local developer habits and assume those protections carry into packaging. They do not, because build tools frequently operate on the workspace state, not on the intended release boundary.
Decision rule: If the file contains credentials, tokens, keys, or environment-specific access material, prioritise removal from the artifact and rotation of the exposed value before debating whether the build rule was “supposed” to include it.
Practitioner takeaway: The reliable test is simple: if a local secret file shows up in the shipped artifact, the pipeline has already crossed the exposure boundary and needs release-path remediation, not just repository cleanup.
Related resources from NHI Mgmt Group
- How should security teams decide whether JIT access is safe for non-human identities?
- How can security teams tell whether secret exposure has become a propagation risk?
- How can security teams tell whether secret exposure from package installs is contained?
- How can security teams tell whether secret management is actually working?