CVE-2026-120306
Beta9 turns each shell command in a tenant image definition into a Dockerfile RUN line and executes it with Buildah on the build worker. The worker image sets BUILDAH_ISOLATION=chroot, and no buildah invocation passes --isolation, so the step only changes its filesystem root. It keeps the worker pod's PID, network, IPC, and user namespaces, runs as uid 0, and holds CAP_DAC_OVERRIDE. PID 1 in that procfs is the worker entrypoint, so /proc/1/root is the worker container's filesystem and is writable. That filesystem contains the runc, buildah, and runsc binaries the worker uses to start tenant containers, the worker's Kubernetes service account token, and the host directories mounted into the pod. Worker pods are privileged. Clip v2 layered builds are the default, so a tenant with a workspace token reaches this by submitting one image build. The read-only proof confirmed the shared namespaces, CAP_DAC_OVERRIDE, and that the worker's runc binary is visible at /proc/1/root. Fixed in worker 0.1.756: Buildah RUN steps, including the WORKDIR mkdir, use OCI isolation with private PID, IPC, and network namespaces, and tenant ARG values are passed only into the build container.
Executive briefing
This record describes a reported software or hardware weakness. The description and CVSS rating are source metadata; practical risk depends on whether your environment uses an affected product/version and whether the vulnerable component is reachable and configured in an exploitable way.
Severity & exploitability
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Impacted products and platforms
Specific affected product configurations are not currently available in the NVD record. Review vendor advisories and validate applicability against your asset inventory.
How it works and what it could affect
The NVD description is the authoritative short summary currently available for this record. A detailed technical mechanism is not inferred when the source record does not provide one.
Weakness classification: CWE-269CWE-653
Review the CVSS attack characteristics above to understand whether exploitation is network/local, whether privileges or user interaction are required, and which confidentiality, integrity or availability impacts are scored.
Remediation and recommended response
- Identify exposure: compare the affected product and version ranges below with your asset inventory, software bill of materials, endpoint inventory and externally exposed services.
- Remediate: review the linked vendor security advisory or patch notes, upgrade to a fixed release, or apply the vendor-provided workaround if an upgrade cannot be completed.
- Mitigate while patching: restrict network access to the vulnerable service, disable the affected feature where operationally safe, and monitor vendor/CERT advisories for updated guidance.
- Validate: confirm the fixed version or mitigation on representative systems, run a vulnerability rescan, and retain change evidence.
Vendor remediation / security advisories
Exploit intelligence & references
No CISA KEV match is recorded in the latest successful catalog refresh. This is not a guarantee that public proof-of-concept code or exploitation does not exist.
- reefs@jfrog.com vendor
- reefs@jfrog.com vendor
- reefs@jfrog.com vendor
- reefs@jfrog.com vendor
Sources: NVD and CISA KEV when available. Vendor confirmation remains the final authority for fixed versions and workarounds.