Tag: security vulnerability

Daily Updates

My prediction that weekly updates are going to be a thing of the past WAY more quickly than the monthly patch and reboot became insufficient: I switched to daily updates at home. Had at least 40 updates each night since! This host runs sendmail and Apache HTTPD on a Linux OS – not a million different applications or anything.

​[lisa@fedora5 ~]# dnf history list
ID Command line              Date and time       Action(s) Altered
67 dnf update                2026-09-18 02:39:22                53
66 dnf update                2026-09-17 02:21:58                44
65 dnf update                2026-09-16 02:44:46                41
64 dnf update                2026-09-15 02:23:13                46

 

Brinqa Remediation – mDNS

Some systems were found to be responding to mDNS requests (5353/udp). Linux hosts were running the avahi-daemon which provides this service. As the auto-discovery service is not used for service identification, the avahi-daemon was disabled.

Confirm response is seen on 5353/udp prior to change:

nmap -P0 -p 5353 -sU hostname.example.net

SSH to host identified as responding to mDNS requests. Disable the avahi-daemon then stop the avahi-daemon:

systemctl disable avahi-daemon
systemctl stop avahi-daemon

 

Verify that 5353/udp is no longer open by repeating the nmap command.

Fin.