Summary: The latest versions of the “xz” tools and libraries contain malicious code that appears to be intended to allow unauthorized access. Specifically, this code is present in versions 5.6.0 and 5.6.1 of the libraries. Fedora Linux 40 users may have received version 5.6.0, depending on the timing of system updates. Fedora Rawhide users may have received version 5.6.0 or 5.6.1.
Yeah, it looks like that little Jenga block from the xkcd meme was XZ and a bunch of infrastructure is gonna have issues because of it.