GHSA-fjv8-j4p5-cr9m

## Summary A sandbox volume reference (`volumeId`, which may also be a volume name) was forwarded to the runner and used to build the host bind-mount source path without confinement. A reference containing path-traversal sequences could in principle resolve the mount source outside the intended per-volume base directory.

## Impact Had the traversal been reachable, an authenticated user could have caused the runner to bind-mount an unintended host path into their sandbox, with a worst-case impact of read and write access to other tenants' volume data (per-volume FUSE mounts are world-readable and writable).

Important: this path was not exploitable in any released version. A volume reference is validated against the database before it reaches the runner, and the volume id column is a UUID type, so a reference containing traversal sequences is rejected at validation time and the request fails before any mount is constructed. We could not reproduce cross-tenant access or an out-of-base host mount on a released build; the observable effect of the documented payload was a server-side validation error. Severity is assessed as Medium on that basis.

## Patches Fixed in v0.186.0. Volume references are now resolved to the canonical volume UUID server-side before reaching the runner, so a name can never flow downstream as a path component, and the runner confines the mount source to the volume base directory and rejects any non-UUID reference.

## Workarounds Upgrade to v0.186.0 or later. No configuration workaround is required for released versions, which were not exploitable.

## Credit Reported by @vnth4nhnt from CyStack.