Do you know what AppArmor is?

AppArmor is a Mandatory Access Control (MAC) system for Linux that restricts application capabilities by defining profiles with permissions for accessing files, network resources, and other system objects. Unlike traditional Access Control Lists (ACLs), AppArmor operates at the application level, allowing processes to be isolated and potentially malicious actions to be prevented.

AppArmor profiles specify what operations are permitted for a specific application, such as reading or writing to certain directories. If an application attempts to perform an action outside its profile, it is blocked.

An example of a simple AppArmor profile for an application:

/usr/bin/myapp {
  # Allow reading configuration files
  /etc/myapp/** r,
  # Allow writing to log directory
  /var/log/myapp/** w,
  # Deny everything else
  deny /**,
}

AppArmor is often used to enhance the security of servers and containers, providing an additional layer of protection without needing to modify the applications themselves.