| name | CIS Ubuntu 14.04 LTS - 2.2.3 Ensure Avahi Server is not enabled |
| description | Verify that Avahi mDNS/DNS-SD daemon is disabled to reduce attack surface |
| category | cis-os-hardening |
| version | 2.1.0 |
| author | cyberstrike-official |
| tags | ["cis","ubuntu","ubuntu-14.04","level-1","scored","services"] |
| cis_id | 2.2.3 |
| cis_benchmark | CIS Ubuntu Linux 14.04 LTS Benchmark v2.1.0 |
| tech_stack | ["ubuntu","linux"] |
| cwe_ids | [] |
| chains_with | [] |
| prerequisites | [] |
| severity_boost | medium |
2.2.3 Ensure Avahi Server is not enabled (Scored)
Profile Applicability
- 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 disable the service to reduce the potential attack surface.
Audit Procedure
Run the following commands to verify no start conditions listed for avahi-daemon:
initctl show-config avahi-daemon
Verify the output shows avahi-daemon with no start conditions.
Expected Result
The avahi-daemon service should have no start conditions listed.
Remediation
Remove or comment out start lines in /etc/init/avahi-daemon.conf:
Default Value
Avahi may be enabled by default on desktop installations.
References
- CIS Controls: 9.1 Limit Open Ports, Protocols, and Services
Profile
- Level 1 - Server
- Level 1 - Workstation