It would appear that the package archive of the KDE Neon operating system was misconfigured in such a way that it could allow anyone to upload any package to it. Most probably, no one uploaded any package there, but, just in case, the maintainers have emptied the archives and remove all the ISO images. The issue was fixed, and, at the moment of writing this article, the KDE Neon package archives are being rebuilt, and new ISO images will be re-generated shortly. As such, users of the GNU/Linux distribution are being urged to upgrade their installations to the latest packages as soon as the software repositories are up and running.