Answer in brief
CVE-2026-120308 records a Critical severity (CVSS 9.9) vulnerability in Beta9 host filesystem exposure via volume path traversal. The current sources do not mark it as known exploited. The current feed maps beam-cloud/github.com/beam-cloud/beta9 (generic), beam-cloud/github.com/beam-cloud/beta9 (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 9.9. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps beam-cloud/github.com/beam-cloud/beta9 (generic), beam-cloud/github.com/beam-cloud/beta9 (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| beam-cloud/github.com/beam-cloud/beta9generic | >=0 <0.1.776 | 0.1.776 |
| beam-cloud/github.com/beam-cloud/beta9generic | >=0 <0.1.756 | 0.1.756 |
Published upstream
Nov 1, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Nov 1, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Nov 1, 2026
A Beta9 tenant can attach a volume when deploying a function, endpoint, or task queue. The gateway builds the host path by joining the shared volumes root, the workspace name, and the volume identifier from the stub configuration. Nothing checks that the identifier names a volume that workspace owns. Parent-directory segments in the identifier collapse the joined path to the worker's filesystem root, and the worker bind-mounts that path into the sandbox read-write unless the volume was explicitly marked read-only. A tenant with a workspace token can therefore read and write the worker's files, including other tenants' volumes stored on that machine. Confirmed against gateway 0.1.769 and worker 0.1.745. Fixed in gateway 0.1.776 and worker 0.1.756: volume identifiers and mount paths are validated before a mount is built, including for stubs saved before the check existed, and the gateway rejects a volume that does not exist or is not owned by the workspace.
Quoted source text, attributed separately from HOL analysis.