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Critical 9.9

Beta9 workerにコンテナ脱出の脆弱性、修正版あり

CVE-2026-120307 First seen on SecPulse

Summary

Beta9のworkerに、サンドボックスの利用者がホスト側のファイルを読み書きできる脆弱性が見つかりました。複数の利用者にBeta9を使わせている組織は、worker 0.1.756へ更新し、サービスアカウントの権限も見直してください。

AI summary

Produced by SecPulse using an external AI model; it may contain mistakes. Check the original description and references below before acting on it.

Beta9のworkerに、サンドボックスの利用者がホスト側のファイルを読み書きできる脆弱性が見つかりました。複数の利用者にBeta9を使わせている組織は、worker 0.1.756へ更新し、サービスアカウントの権限も見直してください。

Affected packages

EcosystemPackageAffectedFixed
beam-cloud Beta9 worker
< 0.1.756
0.1.756
Original description The description as published by the source.

The Beta9 worker serves the sandbox file API from outside the container. getHostPathFromContainerPath turns the tenant's container path into a worker path. If the unresolved path starts with a mount destination, including the default upload mount at /tmp/.beta9, the remainder is joined onto that mount's source with filepath.Join, which cleans parent-directory segments after the prefix check. A long enough run of those segments names any absolute path on the worker. A path that matches no mount is joined onto the container root and opened in the worker's own filesystem, so an absolute symbolic link such as /var/run pointing at /run is followed against the worker root. Upload, download, stat, list, find-in-files, replace-in-files, and delete-file all call this helper. A tenant with a workspace token and one running sandbox can read, write, list, and delete files on the hosting worker as root, including files of other tenants on that machine. A read-only proof downloaded the worker pod's Kubernetes service account token through the file API for a path that did not exist inside the sandbox. In the shipped remote-node manifests that service account is bound to cluster-admin. Fixed in worker 0.1.756: sandbox file operations and workspace sync open paths with os.OpenRoot, so parent-directory and symlink lookups stay inside the container root or the mount source.

Source: CVE.org (CVE Program・cvelistV5) NVD GitHub Advisory

References

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