CVE-2026-93987

Overview

rclone versions 1.56.0 through 1.75.0 contain a path traversal vulnerability in the Docker volume plugin implementation. Specifically, the newVolume() and restoreState() functions fail to properly validate attacker-supplied volume names against the root directory before mounting. This flaw allows unauthorized directory creation and filesystem mounts outside the intended base path.

Description

rclone versions 1.56.0 through 1.75.0 contain a path traversal vulnerability in the `rclone serve docker` volume plugin. newVolume() in cmd/serve/docker/volume.go computes a volume's mountpoint as filepath.Join(drv.root, name) from the attacker-supplied `name` field of a Docker VolumeDriver.Create request without verifying that the result stays within drv.root (default /var/lib/docker-volumes/rclone), and checkMountpoint() then creates that directory with file.MkdirAll before mounting. A volume name containing enough `..` components (e.g. "../../../../../../etc") therefore resolves outside the base directory, allowing anyone able to submit a VolumeDriver.Create request to the plugin socket — normally the Docker daemon, or a workload that can request named volumes in a multi-tenant orchestration setup — to make the privileged rclone plugin process create a directory and mount a remote filesystem specified in the same request at an arbitrary host path, shadowing or disrupting system directories. The advisory notes Volume.restoreState() had the same missing validation when reloading persisted volume state. Fixed in 1.75.1.

Impact

This vulnerability impacts confidentiality, integrity, and availability by allowing unauthorized actors who can submit Docker VolumeDriver requests to create directories and mount remote filesystems at arbitrary host paths. In multi-tenant environments, this could lead to system file shadowing, disruption of critical services, or unauthorized data access. Only systems running the rclone Docker volume plugin and exposing the socket to untrusted workloads are affected.

Remediation

Upgrade rclone to version 1.75.1 or later where path validation checks are correctly implemented. Ensure proper access controls are placed on the Docker volume plugin socket to restrict which workloads and users can submit volume creation requests.

Risk context

The vulnerability is rated as medium severity with a CVSS v3 score of 3.4 and a CVSS v4 score of 4.6. No EPSS data is currently available, and exploitation requires local access or the ability to submit specific API requests to the plugin socket.

Affected products

• rclone 1.56.0 to 1.75.0