Docker Sandboxes Vulnerabilities Let Malicious Guests Escape Workspace and Access Host Files
Docker fixed two symlink-race flaws in Docker Sandboxes, CVE-2026-77179 and CVE-2026-79994, letting malicious guests escape the workspace and read host files; fixed in 0.42.0.
Docker patched CVE-2026-77179 (Critical) and CVE-2026-79994 (High) in Docker Sandboxes 0.42.0, released September 7. Both are time-of-check-to-time-of-use symlink races: CVE-2026-77179 in the macOS virtio-fs host server (versions 0.28.0 to before 0.42.0) can allow a malicious guest to read or modify arbitrary host files and potentially achieve code execution, while CVE-2026-79994 in the guest-to-host Unix socket relay (0.37.0 to before 0.42.0) can redirect host connections to arbitrary AF_UNIX sockets. Docker recommends upgrading and, as interim mitigation, using clone mode and avoiding read-write host mounts.