CVE-2026-53392

A flaw was found in the Linux kernel's NFSv4 (Network File System version 4) flexfiles component. This vulnerability occurs when the ff_layout_alloc_lseg() function processes a malformed flexfiles layout that specifies a zero filehandle version count. An attacker could exploit this by providing a specially crafted flexfiles layout, leading to a null-pointer dereference and ultimately causing a kernel panic, resulting in a Denial of Service (DoS) for the system.

This vulnerability is rated as Moderate severity because triggering the issue requires a client to mount and interact with a compromised or rogue NFS server, preventing arbitrary network-based attacks against default configurations. In Red Hat Enterprise Linux environments, the impact is confined to a local kernel crash and denial of service caused by handling invalid layout structures during pNFS operations. Deployments that only attach to trusted storage infrastructure or do not utilize flexfiles layouts remain unaffected.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.