SB20260626155 - Improper control of a resource through its lifetime in Linux kernel io_uring

Description

This security bulletin contains information about 1 vulnerability.

1) Improper control of a resource through its lifetime (CVE-ID: CVE-2026-53191)

CWE-ID: CWE-664 - Improper control of a resource through its lifetime

CVSSv4: 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/E:U/U:Clear

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

The vulnerability exists due to improper state management in io_uring bundle recv handling in io_uring/net when processing bundle recv retries with provided buffer rings in incremental mode. A local user can trigger partial buffer consumption across retry iterations to cause a denial of service.

Userspace may wrongly advance the ring head past an entry the kernel still uses.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/0bbc9481f970b0b4ddb08cfa464db1cc93b74b56
• https://git.kernel.org/stable/c/4973232a67e4137ab9399f504f7f2bdd847f96d2
• https://git.kernel.org/stable/c/ed46f39c47eb5530a9c161481a2080d3a869cfaf
• https://git.kernel.org/stable/c/f40570fda3f3a1f96aeaa4aef665ba274b2810b5