SB20260727144 - Improper resource shutdown or release in Linux kernel io_uring

Description

This security bulletin contains information about 1 vulnerability.

1) Improper resource shutdown or release (CVE-ID: CVE-2026-64426)

CWE-ID: CWE-404 - Improper Resource Shutdown or Release

CVSSv4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]

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

The vulnerability exists due to improper resource shutdown or release in io_uring NOP handling when processing a NOP request with IOSQE_FIXED_FILE set without IORING_NOP_FIXED_FILE. A local user can submit a crafted io_uring NOP request to cause a denial of service.

The issue results in a file reference leak because a normally acquired file reference is not released on completion.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/2564ca2e31bd8ee8348362941af2ee4671e487ca
• https://git.kernel.org/stable/c/722869fcff598fad20d5ab79c305897a7534708b
• https://git.kernel.org/stable/c/7267717f35787167fcce4bc14f6ef3fa06682dcf