Within the past 12 hours or so all of our builds are failing due to a new 401 error when trying to download/use a plugin in our pipeline builds.

The URL that gives a 401 is: https://repo.jenkins-ci.org/maven-repo1/io/qameta/allure/allure-commandline/2.13.3/allure-commandline-2.13.3.zip

I have heard reports from others in chat that they are also having the same 401 error with different versions of the same plugin.

If you browse the parent folder https://repo.jenkins-ci.org/maven-repo1/io/qameta/allure/allure-commandline/2.13.3/ it does not show the .zip file at all, so I thought that possibly the file did not exist and the 401 error was just misleading. If I point the url to https://repo.jenkins-ci.org/maven-repo1/io/qameta/allure/allure-commandline/2.13.3/foo.zip then that gives a 404 as expected. So this means that the Allure .zip file DOES exist, and it is returning a 401 for some reason.