CVE-2023-0240 HIGH

CVE-2023-0240: Use after free in io_uring in the Linux Kernel

Vendor Linux
Product Linux Kernel
Weakness CWE-416
Published January 30, 2023
Last update August 2, 2024

CVSS base score

7.8/10
Attack vector Local
Attack complexity Low
Privileges required Low
User interaction None
Confidentiality High
Integrity High

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

What the vulnerability does

01Description

There is a logic error in io_uring's implementation which can be used to trigger a use-after-free vulnerability leading to privilege escalation. In the io_prep_async_work function the assumption that the last io_grab_identity call cannot return false is not true, and in this case the function will use the init_cred or the previous linked requests identity to do operations instead of using the current identity. This can lead to reference counting issues causing use-after-free. We recommend upgrading past version 5.10.161.

Key dates

02Disclosure timeline

January 30, 2023 CVE published
August 2, 2024 Record updated