From Terminal in cPanel or from an SSH session as root (or an account with backup restoring privileges), navigate to the folder the cPanel backup files are stored.
From that folder, run the following command:
for i in *; do /scripts/restorepkg --skipres --restricted $i; done;
–skipres will stop the restore from assigning reseller privileges if the backup contained them.
–restricted will restore the backup in restricted mode. This should be done when restoring a backup not created on the local server or a cPanel backup file that is from an untrusted source.