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1. Embed this notice
   Lukas (karotte@chaos.social)'s status on Saturday, 19-Jul-2025 02:07:34 JST Lukas

   Mildly cursed factoid about UNC paths:

   - UNC Paths can contain IP addresses such as \\192.168.1.1\share
   - IPv6 addresses are supported as well
   - IPv6 addresses contain colons
   - can't have colons in Windows paths since colons are reserved for drive letters

   So Microsoft came up with the the ipv6-literal.net domain that's special-cased by Windows so you can to write IPv6 addresses in UNC paths as 2a0e-3c0--21.ipv6-literal.net without it hitting any resolvers.

   • Haelwenn /элвэн/ :triskell: likes this.
   • GreenSkyOverMe (Monika) and Rich Felker repeated this.
   • Embed this notice
     ✧✦Catherine✦✧ (whitequark@mastodon.social)'s status on Saturday, 19-Jul-2025 02:07:33 JST ✧✦Catherine✦✧

     in reply to

     @karotte that's horrifying. thanks

   • Embed this notice
     rootfake (rootfake@mastodon.social)'s status on Saturday, 19-Jul-2025 04:25:27 JST rootfake

     in reply to

     • ✧✦Catherine✦✧

     @whitequark @karotte Thanks, I hate it!

   • Embed this notice
     Lukas (karotte@chaos.social)'s status on Saturday, 19-Jul-2025 07:37:12 JST Lukas

     in reply to

     • Christian Berger DECT 9314

     Turns out, it's worse than this: The ipv6-literal.net shenanigans aren't limited to UNC paths.

     It works in all places:
     > ping 2a0e-3c0--21.ipv6-literal.net

     Pinging 2a0e:3c0::21 with 32 bytes of data:

     Also works in browsers: http://2a0e-3c0--21.ipv6-literal.net/

     Thanks to @casandro for asking.

   • Embed this notice
     Christian Huitema (huitema@social.secret-wg.org)'s status on Saturday, 19-Jul-2025 07:38:07 JST Christian Huitema

     in reply to

     • Kevin Beaumont
     • Axel ⌨🐧🐪🚴😷 | #WeAreNatenom
     • Christian Berger DECT 9314

     @xtaran @karotte @casandro @GossiTheDog

     That's an old one! We came up with it for IPv6 when I was working at Microsoft. I think it was introduced in Windows XP SP1. We were worried that typing addresses like 2001:2:3::abcd was not going to work well in a variety of user interfaces, hence the "2001-2-3--abcd.ipv6-literal.net" hack. One of the team members (maybe me, not sure now) registered it on a personal account, and then transferred ownership to Microsoft before shipping.

   • Embed this notice
     Axel ⌨🐧🐪🚴😷 | #WeAreNatenom (xtaran@chaos.social)'s status on Saturday, 19-Jul-2025 07:38:08 JST Axel ⌨🐧🐪🚴😷 | #WeAreNatenom

     in reply to

     • Kevin Beaumont
     • Christian Berger DECT 9314

     @karotte @casandro: The domain ipv6-literal.net doesn't look as if it belongs to Microsoft (as @GossiTheDog already mentioned in his posting). It is parked at GoDaddy.

   • Embed this notice
     Jona Joachim (jaj@mastodon.social)'s status on Saturday, 19-Jul-2025 17:22:09 JST Jona Joachim

     in reply to

     @whitequark
     Let's hope they will never forget to renew that domain
     @karotte

   • Embed this notice
     Rich Felker (dalias@hachyderm.io)'s status on Sunday, 20-Jul-2025 02:00:53 JST Rich Felker

     in reply to

     @karotte Wow, they're literally hijacking a domain they don't own to do this, too.