SB2026081548 - NULL pointer dereference in Linux kernel fs

Description

This security bulletin contains information about 1 vulnerability.

1) NULL pointer dereference (CVE-ID: CVE-2026-74400)

CWE-ID: CWE-476 - NULL Pointer Dereference

CVSSv4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to a NULL pointer dereference in bpf_set_dentry_xattr, bpf_remove_dentry_xattr, and related xattr permission checks when handling a negative dentry. A local user can pass a negative dentry to trigger a kernel crash or warning-induced panic to cause a denial of service.

Systems with panic_on_warn enabled may panic when the warning path is reached.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/0160edf2af51c5fde742973742c5d10497901b21
• https://git.kernel.org/stable/c/07410646f6ff1d23222f105ccab778957d401bbe
• https://git.kernel.org/stable/c/e003f3a4be738f650e283e92d07017c3fef8da52