V-260937

Discussion

Seccomp filtering provides a means for a process to specify a filter for incoming system calls. The default seccomp profile works on a whitelist basis and allows 311 system calls, blocking all others. It must not be disabled unless it hinders the container application usage. The default seccomp profile blocks syscalls, regardless of --cap-add passed to the container. A large number of system calls are exposed to every user and process, with many of them going unused for the entire lifetime of the process. Most of the applications do not need all the system calls and thus benefit by having a reduced set of available system calls. The reduced set of system calls reduces the total kernel surface exposed to the application and thus improvises application security. When running a container, it uses the default profile unless it is overridden with the --security-opt option.

Check Content

When using Kubernetes orchestration, this check is Not Applicable.

For Swarm orchestration, to ensure the default seccomp profile is not disabled, log in to the CLI:

Linux: As an MKE Admin, execute the following command using a Universal Control Plane (MKE) client bundle:

docker ps --quiet --filter "label=com.docker.ucp.version" | xargs docker inspect --format '{{ .Id }}: SecurityOpt={{ .HostConfig.SecurityOpt }}' 

If seccomp:=unconfined, then the container is running without any seccomp profiles and this is a finding.