I didn't even realize 0.0.0.0 was a valid address to enter into a browser! TIL.
this post was submitted on 31 Jan 2025
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On Linux it is just a catch all address (listen on all interfaces)
Elsewhere it doesn't do anything since I don't believe it is part of the networking standards
Yeah I'm familiar with that part, I just meant in context of a browser being able to connect to it.
If I were implementing it, I'd just list all interfaces on the machine and see if there's a service bound to it on the given port. There's probably only one, but it's technically undefined behavior I think.
What is the use case for 0.0.0.0
Just in case you want to do nothing, nowhere in particular.
0.0.0.0 binds to all addresses on the machine for servers, but I don't know what a browser would do when trying to resolve it. I guess look at all addresses on the machine and see if anything has bound to the indicated port on that address? First one it finds wins?
I just wish they'd stop blocking http requests on lan addresses honestly.
Thanks for the suggestions. While I was investigating I ended up looking and had a proxy issue. Obviously a problem on my part.
Firefox doesn't block http at all
Try the Firefox Developer version. No addons.
EDIT: Thanks for the suggestions. While I was investigating I ended up looking and had a proxy issue. Obviously a problem on my part.
That would kill development, because accessing http services locally is something pretty much only developers do. What is the error message?
Unable to connect
Firefox can’t establish a connection to the server at 192.168.2.210.
The site could be temporarily unavailable or too busy. Try again in a few moments.
If you are unable to load any pages, check your computer’s network connection.
If your computer or network is protected by a firewall or proxy, make sure that Firefox Developer Edition is permitted to access the web.
I don't see an error in the log about the specific page I am trying to access, but another had a link to https://support.mozilla.org/en-US/kb/https-only-prefs
I don't think they ware going to start disabling http. Http is needed in a lot of cases to get https plus there are still use cases for http like testing.
Have you fired up Wireshark and looked at what port it is connecting to?
Thanks for the suggestions. While I was investigating I ended up looking and had a proxy issue. Obviously a problem on my part.
And of course adding an exception or turning it off doesn't work either.
Perhaps a bug then? AFAIK, "developer edition" is basically just nightly.
Pretty sure you have an addon doing that, because Firefox doesn't.
Firefox Developer with no addons
Do you have standard Firefox with default options that does this? This has not been my experience.
You could try out with a new profile if it works out the same.
I just tried to use the Developer version. With no addons.
Could you share a link for me to read up more on this?
I was trying to use the Firefox Developer version. Just straight up refused.
Fine by me. I self-host a lot of stuff but never used 0.0.0.0 for browsing, so I just disabled it here to try it out.
The linked blog post explains about the vulnerability, I thought it was quite interesting.
Shit I used it access the interdimensional cable TV.