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cis-docker-5.6

DevOps & Security
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Ensure sensitive host system directories are not mounted on containers

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Source SKILL.md: https://github.com/CyberStrikeus/CyberStrike/blob/HEAD/.cyberstrike/skill/CIS_benchmarks/Server_Software/Docker/CIS_Docker_Benchmark_v1.8.0/cis-docker-5.6/SKILL.md

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5.6 Ensure sensitive host system directories are not mounted on containers (Manual)

Profile Applicability

  • Level 1 - Docker - Linux

Description

You should not allow sensitive host system directories such as those listed below to be mounted as container volumes, especially in read-write mode.

/
/boot
/dev
/etc
/lib
/lib64
/proc
/sys
/usr

Rationale

If sensitive directories are mounted in read-write mode, it could be possible to make changes to files within them. This has obvious security implications and should be avoided.

Impact

None.

Audit Procedure

You should run the following command:

docker ps --quiet --all | xargs docker inspect --format='{{ .Id }}: Volumes={{ .Mounts }}'

This command returns a list of currently mapped directories and indicates whether they are mounted in read-write mode for each container instance.

Remediation

You should not mount directories which are security sensitive on the host within containers, especially in read-write mode.

Default Value

Docker defaults to using a read-write volume but you can also mount a directory read-only. By default, no sensitive host directories are mounted within containers.

References

  1. https://docs.docker.com/storage/volumes/

CIS Controls

v8

3 Data Protection

Develop processes and technical controls to identify, classify, securely handle, retain, and dispose of data.

v7

13 Data Protection

Data Protection