Implant Internal Image
Implanting an internal image introduces malicious content into reusable cloud or container images.
Reusable images can carry persistent changes
Implanting an internal image introduces unauthorized content into a reusable cloud or container image within the environment. Later workloads created from that image may inherit the change. The image's role as a trusted starting point makes provenance and promotion controls particularly important.
This differs from compromising one running workload. A modified source image can affect future deployments even after the first affected instance is removed. Investigators should establish which image was changed, how it was distributed, and which workloads actually used it.
A trusted base image changes
In a fictional academy, new servers created from an internal image begin showing the same unexplained component. The analyst reviews image identifiers, creation and modification records, build or capture history, registry activity, and deployment references.
An approved maintenance update might explain the change. Compare the artifact and configuration with the reviewed build process and responsible owner's records. A familiar image name or tag is insufficient because labels can point to different content over time.
The team identifies when the changed image became available and which deployments referenced that specific artifact. Do not assume every workload with a similar name inherited the same version.
Follow provenance through deployment
Preserve the suspect image and metadata through controlled handling, alongside trusted comparison material where available. Avoid launching it in production to inspect behavior. Use an authorized isolated analysis process appropriate to its potential risk.
Image creation or modification establishes an artifact change. Deployment and runtime evidence are needed to determine where the change executed. Separate those stages when scoping impact.
Build Image on Host describes another artifact-creation path, while Deploy Container covers workload introduction. Supply Chain Compromise addresses a broader delivery relationship and should not be assumed solely from an internal image change.
Replace the source and affected instances
Restrict the authority that changed the image, remove it from approved deployment paths as justified, and rebuild from a reviewed trusted source. Review already running workloads and other copies because changing a registry label does not automatically replace existing instances.
Coordinate restoration with service owners and define checks for image provenance, workload behavior, and exposed credentials. The access that allowed implantation also requires investigation.
For practice, compare an approved base-image patch with a fictional unreviewed image modification followed by three deployments. Identify the artifact, approval, registry, deployment, and runtime evidence needed to establish scope. Incident response coordinates the replacement work, and Incident reporting and handover distinguishes workloads created from the image from those merely capable of using it.
Related concepts
References & further reading
Original explanations, with primary references for deeper study.
MITRE ATT&CK T1525: Implant Internal Image