Nine-Year-Old RefluXFS Linux Flaw Gives Local Users Root on Default RHEL Installs

RefluXFS, a Linux kernel flaw disclosed on July 22 and tracked as CVE-2026-64600, lets an unprivileged local user overwrite root-owned files on an XFS filesystem and gain persistent root access. Qualys said default installations of Red Hat Enterprise Linux and its derivatives, Fedora Server, and Amazon Linux can meet the conditions for exploitation.