CVE-2026-78410 — util-linux: restricted bind mounts can redirect the source

A flaw in util-linux allows a local unprivileged user to replace the source of a restricted bind mount or a writable ancestor of that source. This can redirect SUID mount(8) to bind another host directory; if X-mount.owner, X-mount.group, or X-mount.mode is configured, root then changes ownership or permissions on the redirected inode.