This is a textbook race condition where restrictive permissions are applied only after a file has been created with weak permissions. Bonus: you get a script to decrypt LUKS encrypted volumes.

Please don't editorialize submission titles.

It's a Tang vulnerability, not a LUKS vulnerability. Clickbait.

This isn't a LUKS bug. It's a bug in a completely different piece of software that most LUKS users have never heard of, which people sometimes use to unlock LUKS volumes.