Description
The guest-to-host Unix-domain socket relay in Docker Sandboxes validates that a socket path is inside an authorized workspace, but later reconnects using the pathname. A malicious guest can replace an intermediate directory with a symlink between validation and connection, causing the host to connect to an arbitrary AF_UNIX socket outside the shared workspace. This can expose data or host-side capabilities provided by the targeted socket.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Docker | Docker Sandboxes | 0.37.0 – < 0.42.0 | 0.42.0 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | docker.io +1 | No fix yet | — |
| Ubuntu 26.04 LTS | docker.io +1 | No fix yet | — |
Show 5 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 24.04 LTS | docker.io +1 | No fix yet | — |
| Ubuntu Pro 22.04 LTS | docker.io +1 | No fix yet | — |
| Ubuntu Pro 20.04 LTS | docker.io +1 | No fix yet | — |
| Ubuntu Pro 18.04 LTS | docker.io | No fix yet | — |
| Ubuntu Pro 16.04 LTS | docker.io | No fix yet | — |
Advisories 1
- WID-SEC-2026-3480 Docker Sandboxes: Mehrere Schwachstellen BSI CERT-Bund (WID) · Sep 20, 2026