It was discovered that runC allowed additional container processes via
runc exec to be ptraced by the pid 1 of the container. This allows the main processes of the container, if running as root, to gain access to file descriptors of these new processes during the initialization, which can lead to container escapes or modification of runC state before the process is fully placed inside the container.
Run yum update docker to update your system.
noarch: docker-devel-1.12.6-1.17.amzn1.noarch docker-pkg-devel-1.12.6-1.17.amzn1.noarch src: docker-1.12.6-1.17.amzn1.src x86_64: docker-1.12.6-1.17.amzn1.x86_64 docker-debuginfo-1.12.6-1.17.amzn1.x86_64