I received a letter multicast DNS vulnerability on my network.
I followed the advice and visited www.virginmedia.com/mdns and the only advice they give is to close port 5353. I checked both Port Triggering and Port Forwarding and there was no port 5353 open for any of my devices so I discarded the letter.
Today I came back home and I have again another letter stating that again VM has been alerted about a multicast dns vulnerability. Given I do not have port 5353 open I am not sure what else they want me to do.
Can anyone make any suggestions? There is no point in sending a letter warning customer about security vulnerability and making a single recommendation which, in my case, is not applicable.
Is there a way for someone to be more specific about which device is causing this issue or is there any more advice that can be given?
I use media server to stream video from my PC or phone etc, I have chromecast too, I access my PC using team viewer and remote control my PS4 and have a WD MyCloud, all password protected but all of this has been in place for ages so do not think it is the reason for the letter. I just recently bought Amazon Echo but, again, I do not think that is the issue.
What else should I do other than ignore the letters?