cgwalters/setuid-shell repository overview

Use this image as a test case for securing Docker image hosts.

First, you can directly run:

/usr/bin/rootshell -p

This is just a copy of bash, which apparently requires an undocumented -p option: http://unix.stackexchange.com/questions/74527/setuid-bit-seems-to-have-no-effect-on-bash⁠

Or, the root password has been removed and you can use the traditional su:

su - root