---
id: CVE-2023-3389
title: >-
  A use-after-free vulnerability in the Linux Kernel io_uring subsystem can be
  exploited to achieve local privilege escalation.


  Racing a io_uring cancel poll request with a linked timeout can cause a UAF in
  a hrtimer.


  We recommend upgrad…
summary: >-
  A use-after-free vulnerability in the Linux Kernel io_uring subsystem can be
  exploited to achieve local privilege escalation.


  Racing a io_uring cancel poll request with a linked timeout can cause a UAF in
  a hrtimer.


  We recommend upgrad…
severity: high
cvss: 7.8
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'
cwe:
  - CWE-416
  - CWE-416
vendor: linux
product: linux_kernel
affected:
  - 'linux_kernel >= 5.10.162, < 5.10.185'
  - 'linux_kernel >= 5.13, < 6.4'
  - ubuntu_linux = 14.04
  - ubuntu_linux = 16.04
  - ubuntu_linux = 18.04
  - ubuntu_linux = 20.04
  - ubuntu_linux = 22.04
  - debian_linux = 10.0
  - debian_linux = 11.0
patched:
  - linux_kernel 6.4
published: '2023-06-28'
updated: '2026-10-14'
sourceUpdated: '2026-10-14T21:17:16.660'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2023-3389'
references:
  - url: >-
      http://packetstormsecurity.com/files/174577/Kernel-Live-Patch-Security-Notice-LSN-0097-1.html
    label: cve-coordination@google.com
  - url: >-
      https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=linux-5.10.y&id=4716c73b188566865bdd79c3a6709696a224ac04
    label: cve-coordination@google.com
  - url: >-
      https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=linux-5.15.y&id=0e388fce7aec40992eadee654193cad345d62663
    label: cve-coordination@google.com
  - url: >-
      https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=ef7dfac51d8ed961b742218f526bd589f3900a59
    label: cve-coordination@google.com
  - url: 'https://kernel.dance/0e388fce7aec40992eadee654193cad345d62663'
    label: cve-coordination@google.com
  - url: 'https://kernel.dance/4716c73b188566865bdd79c3a6709696a224ac04'
    label: cve-coordination@google.com
  - url: 'https://kernel.dance/ef7dfac51d8ed961b742218f526bd589f3900a59'
    label: cve-coordination@google.com
  - url: 'https://lists.debian.org/debian-lts-announce/2023/10/msg00027.html'
    label: cve-coordination@google.com
  - url: 'https://security.netapp.com/advisory/ntap-20230731-0001/'
    label: cve-coordination@google.com
  - url: 'https://www.debian.org/security/2023/dsa-5480'
    label: cve-coordination@google.com
  - url: >-
      http://packetstormsecurity.com/files/174577/Kernel-Live-Patch-Security-Notice-LSN-0097-1.html
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=linux-5.10.y&id=4716c73b188566865bdd79c3a6709696a224ac04
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=linux-5.15.y&id=0e388fce7aec40992eadee654193cad345d62663
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=ef7dfac51d8ed961b742218f526bd589f3900a59
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://kernel.dance/0e388fce7aec40992eadee654193cad345d62663'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://kernel.dance/4716c73b188566865bdd79c3a6709696a224ac04'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://kernel.dance/ef7dfac51d8ed961b742218f526bd589f3900a59'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://lists.debian.org/debian-lts-announce/2023/10/msg00027.html'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://security.netapp.com/advisory/ntap-20230731-0001/'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://www.debian.org/security/2023/dsa-5480'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-794697.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
tags:
  - nvd
epss: 0.00669
epssPercentile: 0.50804
ingestedAt: '2026-10-14T21:57:04.735Z'
---

## Overview

A use-after-free vulnerability in the Linux Kernel io_uring subsystem can be exploited to achieve local privilege escalation.

Racing a io_uring cancel poll request with a linked timeout can cause a UAF in a hrtimer.

We recommend upgrading past commit ef7dfac51d8ed961b742218f526bd589f3900a59 (4716c73b188566865bdd79c3a6709696a224ac04 for 5.10 stable and 0e388fce7aec40992eadee654193cad345d62663 for 5.15 stable).

## Affected

- `linux_kernel >= 5.10.162, < 5.10.185`
- `linux_kernel >= 5.13, < 6.4`
- `ubuntu_linux = 14.04`
- `ubuntu_linux = 16.04`
- `ubuntu_linux = 18.04`
- `ubuntu_linux = 20.04`
- `ubuntu_linux = 22.04`
- `debian_linux = 10.0`
- `debian_linux = 11.0`

## Remediation

Upgrade past the affected range:

- `linux_kernel 6.4`