SB2026072145 - Improper input validation in Linux kernel nfs flexfilelayout

Description

This security bulletin contains information about 1 vulnerability.

1) Improper input validation (CVE-ID: CVE-2026-53392)

CWE-ID: CWE-20 - Improper input validation

CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to improper input validation in ff_layout_alloc_lseg() in the NFSv4 flexfiles layout handling when processing a malformed flexfiles layout body with a zero filehandle-version array count. A remote attacker can send a specially crafted flexfiles layout to cause a denial of service.

The issue can lead to a null pointer dereference and kernel panic.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/2131ed64b767ffa8bcdb3677d90f3964e39aabc8
• https://git.kernel.org/stable/c/2c6bb3c40bc24f6aa8dfbe6fe98c3ad6389203f2
• https://git.kernel.org/stable/c/7779c85028a0676fb190cde4f0c540f4f8e97761
• https://git.kernel.org/stable/c/d8c90c7cc061265d5f2813a1f5c82ef2f4707e67