SB20261023172 - Use-after-free in Linux kernel fs

Description

This security bulletin contains information about 1 vulnerability.

1) Use-after-free (CVE-ID: CVE-2026-98994)

CWE-ID: CWE-416 - Use After Free

CVSSv4: 5.7 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows a local user to potentially cause a denial of service by triggering a kernel use-after-free.

The vulnerability exists due to a use-after-free in statmount_mnt_basic() in fs/namespace.c when processing STATMOUNT_BY_FD requests for an unmounted mount while its parent is concurrently released. A local user can query an unmounted mount retained by a file descriptor during concurrent parent mount teardown to trigger a dereference of freed parent mount memory and potentially crash the kernel.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/98fc6c7b6ca676157d2c780bd0a537b2c10fe08f
• https://git.kernel.org/stable/c/bb46094057520304073130920c223451c2a694a7