Rule ID
SV-254564r1156618_rule
Version
V2R6
CCIs
There are various configuration files, logs, access credentials, and other files stored on the host filesystem that contain sensitive information. These files could potentially be put at risk, along with other specific workloads and components: - API server. - proxy. - scheduler. - controller. - etcd. - Kubernetes administrator account information. - audit log access, modification, and deletion. - application access, modification, and deletion. - container runtime files. If an attacker can gain access to these files, changes can be made to open vulnerabilities and bypass user authorizations inherent within Kubernetes with RBAC implemented. It is crucial to ensure user permissions are enforced down through to the operating system. Protecting file permissions will ensure that if a nonprivileged user gains access to the system they will still not be able to access protected information from the cluster API, cluster configuration, and sensitive cluster information. This control relies on the underlying operating system also having been properly configured to allow only least privileged access to perform required operations. Satisfies: SRG-APP-000133-CTR-000300, SRG-APP-000133-CTR-000295, SRG-APP-000133-CTR-000305, SRG-APP-000133-CTR-000310
File system permissions: 1. Verify correct permissions of the files in /etc/rancher/rke2. cd /etc/rancher/rke2 ls -l all owners are root:root all permissions are 0600 2. Verify correct permissions of the files in /var/lib/rancher/rke2. cd /var/lib/rancher/rke2 ls -l all owners are root:root 3. Verify correct permissions of the files and directories in /var/lib/rancher/rke2/agent. cd /var/lib/rancher/rke2/agent ls -l owners and group are root:root File permissions set to at least 0640 for the following: rke2controller.kubeconfig kubelet.kubeconfig kubeproxy.kubeconfig Certificate file permissions set to 0600: client-ca.crt client-kubelet.crt client-kube-proxy.crt client-rke2-controller.crt server-ca.crt serving-kubelet.crt Key file permissions set to 0600: client-kubelet.key serving-kubelet.key client-rke2-controller.key client-kube-proxy.key The directory permissions to 0700: pod-manifests etc 4. Verify correct permissions of the files in /var/lib/rancher/rke2/bin. cd /var/lib/rancher/rke2/bin ls -l all owners are root:root all files are 0750 5. Verify correct permissions of the directory /var/lib/rancher/rke2/data. cd /var/lib/rancher/rke2 ls -l owners are root:root permissions are 0750 6. Verify correct permissions of each file in /var/lib/rancher/rke2/data. cd /var/lib/rancher/rke2/data ls -l all owners are root:root all files are 0750 7. Verify correct permissions of /var/lib/rancher/rke2/server. cd /var/lib/rancher/rke2/server ls -l all owners are root:root The following directories are set to 0700: cred db tls The following directories are set to 0750: manifests logs The following file is set to 0600: token 8. Verify the RKE2 Server configuration file on all RKE2 Server hosts contain the following: (cat /etc/rancher/rke2/config.yaml) write-kubeconfig-mode: "0600" If any of the permissions specified above do not match the required level, this is a finding.
File system permissions:
1. Fix permissions of the files in /etc/rancher/rke2:
cd /etc/rancher/rke2
chmod 0600 ./*
chown root:root ./*
ls -l
2. Fix permissions of the files in /var/lib/rancher/rke2:
cd /var/lib/rancher/rke2
chown root:root ./*
ls -l
3. Fix permissions of the files and directories in /var/lib/rancher/rke2/agent:
cd /var/lib/rancher/rke2/agent
chown root:root ./*
chmod 0700 pod-manifests
chmod 0700 etc
find . -maxdepth 1 -type f -name "*.kubeconfig" -exec chmod 0640 {} \;
find . -maxdepth 1 -type f -name "*.crt" -exec chmod 0600 {} \;
find . -maxdepth 1 -type f -name "*.key" -exec chmod 0600 {} \;
ls -l
4. Fix permissions of the files in /var/lib/rancher/rke2/bin:
cd /var/lib/rancher/rke2/bin
chown root:root ./*
chmod 0750 ./*
ls -l
5. Fix permissions directory of /var/lib/rancher/rke2/data:
cd /var/lib/rancher/rke2
chown root:root data
chmod 0750 data
ls -l
6. Fix permissions of files in /var/lib/rancher/rke2/data:
cd /var/lib/rancher/rke2/data
chown root:root ./*
chmod 0750 ./*
ls -l
7. Fix permissions in /var/lib/rancher/rke2/server:
cd /var/lib/rancher/rke2/server
chown root:root ./*
chmod 0700 cred
chmod 0700 db
chmod 0700 tls
chmod 0750 manifests
chmod 0750 logs
chmod 0600 token
ls -l
Edit the RKE2 Server configuration file on all RKE2 Server hosts, located at /etc/rancher/rke2/config.yaml, to contain the following:
write-kubeconfig-mode: "0600"
Once the configuration file is updated, restart the RKE2 Server. Run the command:
systemctl restart rke2-server