A Linux engineer finds multiple failed login entries in the security log file for application users. The Linux engineer performs a security audit and discovers a security issue. Given the following:
# grep -iE '*www*|db' /etc/passwd
www-data:x:502:502:www-data:/var/www:/bin/bash
db:x: 505:505:db: /opt/db:/bin/bash
Which of the following commands would resolve the security issue?