Run the following script to disable the udf module: -IF- the module is available in the running kernel: - Create a file ending inconf with install udf /bin/false in the /etc/modprobe.d/ directory - Create a file ending inconf with blacklist udf in the /etc/modprobe.d/ directory - Unload udf from the kernel -IF- available in ANY installed kernel: - Create a file ending inconf with blacklist udf in the /etc/modprobe.d/ directory -IF- the kernel module is not available on the system or pre-compiled into the kernel: - No remediation is necessary #!/usr/bin/env bash { l_mname="udf" # set module name l_mtype="fs" # set module type l_mpath="/lib/modules/**/kernel/$l_mtype" l_mpname="$(tr '-' '_' <<< "$l_mname")" l_mndir="$(tr '-' '/' <<< "$l_mname")" module_loadable_fix() { # If the module is currently loadable, add "install {MODULE_NAME} /bin/false" to a file in "/etc/modprobe.d" l_loadable="$(modprobe -n -v "$l_mname")" [ "$(wc -l <<< "$l_loadable")" -gt "1" ] && l_loadable="$(grep -P -- "(^h*install|b$l_mname)b" <<< "$l_loadable")" if ! grep -Pq -- '^h*install /bin/(true|false)' <<< "$l_loadable"; then echo -e " - setting module: \"$l_mname\" to be not loadable" echo -e "install $l_mname /bin/false" >> /etc/modprobe.d/"$l_mpname".conf fi } module_loaded_fix() { # If the module is currently loaded, unload the module if lsmod | grep "$l_mname" > /dev/null 2>&1; then echo -e " - unloading module \"$l_mname\"" modprobe -r "$l_mname" fi } module_deny_fix() { # If the module isn't deny listed, denylist the module if ! modprobe --showconfig | grep -Pq -- "^h*blacklisth+$l_mpnameb"; then echo -e " - deny listing \"$l_mname\"" echo -e "blacklist $l_mname" >> /etc/modprobe.d/"$l_mpname".conf fi } # Check if the module exists on the system for l_mdir in $l_mpath; do if [ -d "$l_mdir/$l_mndir" ] && [ -n "$(ls -A $l_mdir/$l_mndir)" ]; then echo -e " - module: \"$l_mname\" exists in \"$l_mdir\" - checking if disabled..." module_deny_fix if [ "$l_mdir" = "/lib/modules/$(uname -r)/kernel/$l_mtype" ]; then module_loadable_fix module_loaded_fix fi else echo -e " - module: \"$l_mname\" doesn't exist in \"$l_mdir\" " fi done echo -e " - remediation of module: \"$l_mname\" complete " } Impact: Microsoft Azure requires the usage of udf udf should not be disabled on systems run on Microsoft Azure.

Name	Audit Name	Plugin	Category
1.1.1.7 Ensure udf kernel module is not available	CIS CentOS Linux 7 v4.0.0 L2 Server	Unix	CONFIGURATION MANAGEMENT
1.1.1.7 Ensure udf kernel module is not available	CIS CentOS Linux 7 v4.0.0 L2 Workstation	Unix	CONFIGURATION MANAGEMENT

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