RefluXFS in Linux: a local user may gain root on some standard RHEL systems

Colleagues, I’d like to draw attention to a cybersecurity and Linux vulnerability: RefluXFS (CVE-2026-64600) can allow a local user to obtain root privileges on systems using XFS with reflink=1.

I would first check default installations of RHEL, Fedora Server, and Amazon Linux.

What matters:
- the exploit requires local access and conditions on a single XFS partition;
- the patch is already in place, and vendors are releasing updated kernels;
- after installing the update, a reboot is required for the fix to take effect.

Why it matters: such a flaw can help an attacker establish persistence and increases the risk for multi-user servers.

Have you already checked whether you have XFS with reflink=1?#cybersecurity #Linux #Vulnerability #RHEL