Vulnerability Description
The Docker CLI --use-api-socket flag bypasses Enhanced Container Isolation (ECI) restrictions in Docker Desktop. When ECI is enabled, Docker socket mounts from containers are denied unless explicitly allowed via the admin-settings configuration. However, the --use-api-socket flag adds the Docker socket mount via the HostConfig.Mounts field rather than the HostConfig.Binds field. The ECI enforcement in the Docker Desktop API proxy only inspected Binds, allowing the mount to pass unchecked. This grants a container full access to the Docker Engine socket and, if the host user has logged in to container registries, their authentication credentials. A local attacker with the ability to run Docker CLI commands can exploit this to escape ECI restrictions, access the Docker Engine, and potentially escalate privileges.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Docker | Docker Desktop | >= 4.41.0, < 4.59.0 |
| Apple | Macos | - |
| Linux | Linux Kernel | - |
| Microsoft | Windows | - |
Related Weaknesses (CWE)
References
- https://docs.docker.com/desktop/release-notes/#4590Release Notes
- https://www.zerodayinitiative.com/advisories/ZDI-26-299/Third Party Advisory
FAQ
What is CVE-2026-6406?
CVE-2026-6406 is a vulnerability with a CVSS score of 8.8 (HIGH). The Docker CLI --use-api-socket flag bypasses Enhanced Container Isolation (ECI) restrictions in Docker Desktop. When ECI is enabled, Docker socket mounts from containers are denied unless explicitly ...
How severe is CVE-2026-6406?
CVE-2026-6406 has been rated HIGH with a CVSS base score of 8.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-6406?
Check the references section above for vendor advisories and patch information. Affected products include: Docker Docker Desktop, Apple Macos, Linux Linux Kernel, Microsoft Windows.