I suspect many people _did_ find other ways to connect (indeed I fired my IRC Cloud subscription back up...), but that's not what ultimately brought us* to this decision. Really it came down to not having the funds or staff time to maintain and operate it to the level that was needed.

Echoing you, I am likewise really grateful for all the people who worked on it while it was doable!

* Speaking on behalf of the Matrix.org Foundation here as its Managing Director.

I wrote my own IRC + Matrix client to bridge the channels I operate. I've made the source code available under the terms of the MIT license here: https://github.com/susam/nimb

If you find any issues, bugs, etc. in this tool, please let me know. Although this tool works well for my modest requirements, someone else may find issues while using this tool that I have not encountered yet. In such a case, bug reports, pull requests, patches, etc. are very welcome!

You need to split on (or sanitize) null bytes here: https://github.com/susam/nimb/blob/b40d87ddf2e1134fed4d7380b... and sanitize NUL/CR/LF from the prefix (well, display_name) here: https://github.com/susam/nimb/blob/b40d87ddf2e1134fed4d7380b...

Otherwise you may have a command injection vulnerability similar to what matrix-appservice-irc used to have: https://pktz.fr/matrix/security/2022-appservice-irc-command-... (though with carriage returns instead of null bytes)

Thank you for taking a close look at the source code and highlighting this issue.

> You need to split on (or sanitize) null bytes

Do you mean splitting on (or sanitising of) carriage returns (CR or 0xD) and newlines (LF or 0xA)? I read your security advisory and as far as I understand, the issue occurs due to improper handling of CR and LF characters. I don't see anything about null bytes there.

Null bytes are not allowed in IRC messages: https://modern.ircdocs.horse/#parameters

Some IRC servers (especially those written in C) may interpret it as a line end, so you would have a similar issue

Your security advisory has been quite helpful and I could reproduce the issue involving CR. It is particularly enlightening to know that the null byte could also cause the same issue because some IRC servers may interpret the null byte too as a line ending.

It is late here but I have pushed a quick fix to plug this loophole: <https://github.com/susam/nimb/commit/1c02137>. Review comments, feedback, pull requests, patches, etc. are very welcome! Thank you for this comment thread which has been constructive as well as productive.

I wager many like me just stopped using Libera.chat.

> I wonder whether the July move prompted users to find other ways to connect to Libera.chat besides Matrix, killing usage of the bridge, leading us here.

It certainly, did, I deployed Heisenbridge on my homeserver because I didn't want to go back to having two clients open.