Information
By default, all network traffic is allowed between containers on the same host on the default network bridge. If not desired, restrict all inter-container communication. Link specific containers together that require communication. Alternatively, you can create custom network and only join containers that need to communicate to that custom network.
Rationale:
By default, unrestricted network traffic is enabled between all containers on the same host on the default network bridge. Thus, each container has the potential of reading all packets across the container network on the same host. This might lead to an unintended and unwanted disclosure of information to other containers. Hence, restrict inter-container communication on the default network bridge.
Solution
Edit the Docker daemon configuration file to ensure that icc is disabled. It should include the following setting
'icc': false
Alernatively, run the docker daemon directly and pass --icc=false as an argument.
For Example,
dockerd --icc=false
Alternatively, you can follow the Docker documentation and create a custom network and only join containers that need to communicate to that custom network. The --icc parameter only applies to the default docker bridge, if custom networks are used then the approach of segmenting networks should be adopted instead.
Impact:
Inter-container communication would be disabled on the default network bridge. If any communication between containers on the same host is desired, then it needs to be explicitly defined using container linking or alternatively custom networks have to be defined.
Default Value:
By default, all inter-container communication is allowed on the default network bridge.