Full Report
Docker security advisory (AV26-925)
Analysis Summary
# Vulnerability: Docker Sandboxes Arbitrary File System Access
## CVE Details
* **CVE ID:** Pending / Not specified in advisory (Referenced under Docker Advisory AV26-925)
* **CVSS Score:** Not explicitly provided; High severity implied based on sandbox escape context.
* **CWE:** Likely CWE-22 (Improper Limitation of a Pathname to a Restricted Directory) or CWE-1265 (Unintended Character Encoding/Translation).
## Affected Systems
* **Products:** Docker Sandboxes
* **Versions:** All versions prior to v0.43.0
* **Configurations:** Systems utilizing Docker Sandboxes for isolation of untrusted workloads.
## Vulnerability Description
While the advisory (AV26-925) does not provide a deep technical deep-dive, the fix implemented in the referenced release (v0.43.0) addresses a flaw in how the sandbox handles file system boundaries. The vulnerability typically allows a process within the sandbox to bypass directory restrictions, potentially leading to unauthorized read/write access to the host file system or other isolated environments.
## Exploitation
* **Status:** Not exploited (No reports of active exploitation in the wild as of the advisory date).
* **Complexity:** Medium (Requires the ability to execute code within a sandbox instance).
* **Attack Vector:** Local/Adjacent (The attacker must have access to run tasks within the sandbox).
## Impact
* **Confidentiality:** High (Potential access to sensitive host files).
* **Integrity:** High (Potential to modify host files or configuration).
* **Availability:** Medium (Potential for system instability if critical host files are altered).
## Remediation
### Patches
* **Docker Sandboxes v0.43.0:** This version contains the necessary security fixes to mitigate the identified flaw. Users should upgrade immediately.
### Workarounds
* **Restrict Sandbox Permissions:** Limit the capabilities (`cap-drop`) of containers running within the sandbox.
* **Filesystem Mounts:** Avoid mounting sensitive host directories (like `/etc` or `/var/run/docker.sock`) into the sandbox environment.
## Detection
* **Indicators of Compromise:** Unusual file access patterns originating from the Docker Sandbox process; unexpected directory traversal attempts (e.g., `../` patterns) in container logs.
* **Detection methods and tools:** Audit host-level file access using tools like `auditd` or Falco to monitor for sandbox escapes or unauthorized access to host paths.
## References
* Docker sbx-releases: hxxps[://]github[.]com/docker/sbx-releases/releases/#release-v0.43.0
* Docker security announcements: hxxps[://]docs[.]docker[.]com/security/security-announcements/
* Cyber Centre Advisory (AV26-925): hxxps[://]www[.]cyber[.]gc[.]ca/en/alerts-advisories/docker-security-advisory-av26-925