TMA-DOCKER-3.12
Ensure that the Docker server certificate file permissions are set to 444 or more restrictively
HighLevel 1Automateddocker
Description
The Docker server certificate file must have mode 444 or more restrictive. The path is taken from --tlscert on the dockerd command line or "tlscert" in /etc/docker/daemon.json (default /root/.docker/cert.pem); compliant when no such file exists (TLS not configured).
How it is checked
Audit method: Shell command
shell
args=$(ps -eo args 2>/dev/null) || exit 1; s=$(printf '%s\n' "$args" | grep '[d]ockerd'; cat /etc/docker/daemon.json 2>/dev/null); p=$(printf '%s\n' "$s" | sed -n -e 's/.*--tlscert[= ]\([^ ]*\).*/\1/p' -e 's/.*"tlscert"[[:space:]]*:[[:space:]]*"\([^"]*\)".*/\1/p' | head -n 1); [ -n "$p" ] || p=/root/.docker/cert.pem; [ -e "$p" ] || { echo compliant; exit 0; }; out=$(find "$p" -maxdepth 0 -perm /7333) || exit 1; [ -z "$out" ] && echo compliant || echo "$p"- Expected output
compliant
How it is fixed
Fix method: Guidance or infrastructure patch
chmod 444 <path of the tlscert file> (as configured for dockerd).
Properties
- Operating systems
- Any
- Tags
- dockerpermissionstls
- Reference
- CIS Docker Benchmark v1.9.0 - 3.12 Ensure that the Docker server certificate file permissions are set to 444 or more restrictively
Check this host
Run this on a machine you are allowed to audit. The scan is read-only.
shell
tmaegis scan --target docker