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Fencer Vulns
high 7.8

CVE-2023-3389 json

Use after free in io_uring in the Linux Kernel

published 2023-06-28 3 y ago modified 2026-10-14 25 d ago also EUVD-2023-44056

cvss
7.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.7%
EPSS 0.7% chance of exploitation in 30 days, percentile 52%
public exploits
0
none known

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

Patch / fix

  • Linux Kernel 5.10.185, 6.4
  • Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem V1.1
  • linux Debian 14, Debian 13, Debian 12 6.0.2-1

debian advisories DEBIAN-CVE-2023-3389

  • linux Ubuntu 22.04 LTS 5.15.0-78.85
  • linux-aws Ubuntu 22.04 LTS 5.15.0-1040.45
  • linux-gcp Ubuntu 22.04 LTS 5.15.0-1038.46
  • linux-gke Ubuntu 22.04 LTS 5.15.0-1038.43
  • linux-ibm Ubuntu 22.04 LTS 5.15.0-1034.37
  • linux-kvm Ubuntu 22.04 LTS 5.15.0-1038.43
  • linux-azure Ubuntu 22.04 LTS 5.15.0-1042.49
  • linux-gkeop Ubuntu 22.04 LTS 5.15.0-1024.29

ubuntu advisories UBUNTU-CVE-2023-3389

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • kernel-rt Real Time Module 15 SP5, openSUSE Leap 15.5 5.14.21-150500.13.11.1
  • kernel-syms-rt Real Time Module 15 SP5, openSUSE Leap 15.5 5.14.21-150500.13.11.1
  • kernel-rt_debug Real Time Module 15 SP5, openSUSE Leap 15.5 5.14.21-150500.13.11.1
  • kernel-source-rt Real Time Module 15 SP5, openSUSE Leap 15.5 5.14.21-150500.13.11.1
  • kernel-azure SLE Module for Public Cloud 15 SP5, openSUSE Leap 15.5 5.14.21-150500.33.6.1
  • kernel-syms-azure SLE Module for Public Cloud 15 SP5, openSUSE Leap 15.5 5.14.21-150500.33.6.1
  • kernel-source-azure SLE Module for Public Cloud 15 SP5, openSUSE Leap 15.5 5.14.21-150500.33.6.1
  • dtb-aarch64 openSUSE Leap 15.5 5.14.21-150500.55.7.1

suse advisories SUSE-SU-2023:3302-1SUSE-SU-2023:2892-1SUSE-SU-2023:2871-1SUSE-SU-2023:2831-1SUSE-SU-2023:2820-1SUSE-SU-2023:2803-1

  • kernel CBL-Mariner 2.0 5.15.122.1-2
  • hyperv-daemons CBL-Mariner 2.0 5.15.135.1-1

azure linux advisories AZL-27349AZL-31612

Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2023-3389 updated cvss 5.5

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

  • Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 more Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 more
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

cisa ICSA-23-166-11 updated cvss 7.8

Siemens SIMATIC S7-1500 TM MFP Linux Kernel

Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
total
Assessed
20 mo ago

Exploit prediction

0.67% chance of exploitation in the next 30 days, higher than 52% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD 3.1 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected products

  • Linux Kernel
  • Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem

Classification

Weakness
Technology feeds

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.