Red Hat Security Advisory 2017-0116-01 – Docker is an open-source engine that automates the deployment of any application as a lightweight, portable, self-sufficient container that will run virtually anywhere. The following packages have been upgraded to a newer upstream version: docker. Security Fix: The runc component used by `docker exec` feature of docker allowed additional container processes via to be ptraced by the pid 1 of the container. This allows the main processes of the container, if running as root, to gain low-level access to these new processes during initialization. An attacker can, depending on the nature of the incoming process, leverage this to elevate access to the host. This ranges from accessing host content through the file descriptors of the incoming process to, potentially, a complete container escape by leveraging memory access or syscall interception.