cyberstrikeus 2.2.2 Ensure Avahi Server is not installed (Automated)
Profile
- Level 1 - Server
- Level 1 - Workstation
Description
Avahi is a free zeroconf implementation, including a system for multicast DNS/DNS-SD service discovery. Avahi allows programs to publish and discover services and hosts running on a local network with no specific configuration. For example, a user can plug a computer into a network and Avahi automatically finds printers to print to, files to look at and people to talk to, as well as network services running on the machine.
Rationale
Automatic discovery of network services is not normally required for system functionality. It is recommended to remove this package to reduce the potential attack surface.
Audit Procedure
Command Line
Run the following command to verify avahi-daemon is not installed:
# dpkg-query -s avahi-daemon &>/dev/null && echo "avahi-daemon is installed"
Nothing should be returned.
Expected Result
No output (empty result).
Remediation
Command Line
Run the following commands to remove avahi-daemon:
# systemctl stop avahi-daemon.service
# systemctl stop avahi-daemon.socket
# apt purge avahi-daemon
References
- NIST SP 800-53 Rev. 5: SI-4
CIS Controls
- v8: 4.8 - Uninstall or Disable Unnecessary Services on Enterprise Assets and Software
- v7: 9.2 - Ensure Only Approved Ports, Protocols and Services Are Running