1.7.7 Do not admit containers with dangerous capabilities

Information

Do not generally permit containers with potentially dangerous capabilities.

Rationale:

Containers run with a default set of capabilities as assigned by the Container Runtime. By default this can include potentially dangerous capabilities. By default with Docker as the container runtime the NET_RAW capability is enabled which may be misused by malicious containers.

Ideally, all containers should drop this capability.

There should be at least one PodSecurityPolicy (PSP) defined which prevents containers with the NET_RAW capability from launching.

If you need to run containers with this capability, this should be defined in a separate PSP and you should carefully check RBAC controls to ensure that only limited service accounts and users are given permission to access that PSP.

Solution

Create a PSP as described in the Kubernetes documentation, ensuring that the .spec.requiredDropCapabilities is set to include either NET_RAW or ALL.

Impact:

Pods with containers which run with the NET_RAW capability will not be permitted.

See Also

https://workbench.cisecurity.org/files/2125

Item Details

Category: CONFIGURATION MANAGEMENT

References: 800-53|CM-6b., CSCv6|5.1

Plugin: Unix

Control ID: f4206435ccc4de7a41d7f43b98c780967a2f7b637630bcd7d4a7c8bbb5a9a725