Docker before 1.3.2 allows remote attackers to write to arbitrary files and execute arbitrary code via a (1) symlink or (2) hard link attack in an image archive in a (a) pull or (b) load operation.
Docker before 1.3.1 and docker-py before 0.5.3 fall back to HTTP when the HTTPS connection to the registry fails, which allows man-in-the-middle attackers to conduct downgrade attacks and obtain authentication and image data by leveraging a network position between the client and the registry to block HTTPS traffic.
Docker 1.0.0 uses world-readable and world-writable permissions on the management socket, which allows local users to gain privileges via unspecified vectors.