medium 4.4

CVE-2023-42756 json

Kernel: netfilter: race condition between ipset_cmd_add and ipset_cmd_swap

published 2023-09-28 3 y ago modified 2026-11-07 2 d ago also EUVD-2023-47188

cvss: 4.4; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 19%
public exploits: 0; none known

A flaw was found in the Netfilter subsystem of the Linux kernel. A race condition between IPSET_CMD_ADD and IPSET_CMD_SWAP can lead to a kernel panic due to the invocation of `__ip_set_put` on a wrong `set`. This issue may allow a local user to crash the system.

Patch / fix

fixed in 1 distros 6 links 3

Red Hat Red Hat Enterprise Linux 9 0:5.14.0-427.13.1.el9_4

debian ubuntu red hat opensuse almalinux azure linux

linux Debian 12 6.1.55-1
linux Debian 14, Debian 13 6.5.6-1

debian advisories DEBIAN-CVE-2023-42756

linux Ubuntu 20.04 LTS 5.4.0-165.182
linux Ubuntu 22.04 LTS 5.15.0-87.97
linux-aws Ubuntu 20.04 LTS 5.4.0-1112.121
linux-aws Ubuntu 22.04 LTS 5.15.0-1048.53
linux-gcp Ubuntu 20.04 LTS 5.4.0-1116.125
linux-gcp Ubuntu 22.04 LTS 5.15.0-1045.53
linux-gke Ubuntu 22.04 LTS 5.15.0-1045.50
linux-ibm Ubuntu 20.04 LTS 5.4.0-1059.64

ubuntu advisories UBUNTU-CVE-2023-42756

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 RHEL 9 5.14.0-427.13.1.el9_4
rv RHEL 9 5.14.0-427.13.1.el9_4
perf RHEL 9 5.14.0-427.13.1.el9_4
rtla RHEL 9 5.14.0-427.13.1.el9_4
bpftool RHEL 9 7.3.0-427.13.1.el9_4
libperf RHEL 9 5.14.0-427.13.1.el9_4
kernel-rt RHEL 9 5.14.0-427.13.1.el9_4
kernel-64k RHEL 9 5.14.0-427.13.1.el9_4

red hat advisories RHSA-2024:2394

kernel-source openSUSE Tumbleweed 6.5.6-1.1
kernel-source openSUSE Tumbleweed 6.6.17-1.1

opensuse advisories openSUSE-SU-2024:13305-1 openSUSE-SU-2024:13704-1

kernel AlmaLinux 9 5.14.0-427.13.1.el9_4
rv AlmaLinux 9 5.14.0-427.13.1.el9_4
perf AlmaLinux 9 5.14.0-427.13.1.el9_4
rtla AlmaLinux 9 5.14.0-427.13.1.el9_4
bpftool AlmaLinux 9 7.3.0-427.13.1.el9_4
libperf AlmaLinux 9 5.14.0-427.13.1.el9_4
kernel-rt AlmaLinux 9 5.14.0-427.13.1.el9_4
kernel-64k AlmaLinux 9 5.14.0-427.13.1.el9_4

almalinux advisories ALSA-2024:2394

kernel CBL-Mariner 2.0 5.15.135.1-2

azure linux advisories AZL-30055

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

access.redhat.com/security/cve/CVE-2023-42756 advisory
bugzilla.redhat.com/show_bug.cgi?id=2239848 advisory
seclists.org/oss-sec/2023/q3/242 advisory

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-2023-42756 updated 2026-11-07 cvss 4.4

kernel: netfilter: race condition between IPSET_CMD_ADD and IPSET_CMD_SWAP

Red Hat Enterprise Linux 9 kernel-rt, kernel-rt-kvm, kernel-rt-core, kernel-rt-modules, kernel-rt-debug-kvm, kernel-rt-debug-core, +12 more
affected: workaround, no fix available
Red Hat Enterprise Linux AppStream (v. 9) rv 5.14.0-427.13.1.el9_4, perf 5.14.0-427.13.1.el9_4, rtla 5.14.0-427.13.1.el9_4, kernel-devel-matched 5.14.0-427.13.1.el9_4, kernel-64k-devel-matched 5.14.0-427.13.1.el9_4, kernel-debug-devel-matched 5.14.0-427.13.1.el9_4, +6 more Red Hat Enterprise Linux BaseOS (v. 9) bpftool 7.3.0-427.13.1.el9_4, kernel 5.14.0-427.13.1.el9_4, kernel-64k 5.14.0-427.13.1.el9_4, kernel-core 5.14.0-427.13.1.el9_4, kernel-tools 5.14.0-427.13.1.el9_4, python3-perf 5.14.0-427.13.1.el9_4, +28 more Red Hat Enterprise Linux CRB (v. 9) libperf 5.14.0-427.13.1.el9_4, kernel-debuginfo-common-s390x 5.14.0-427.13.1.el9_4, kernel-debuginfo-common-x86_64 5.14.0-427.13.1.el9_4, kernel-debuginfo-common-aarch64 5.14.0-427.13.1.el9_4, kernel-debuginfo-common-ppc64le 5.14.0-427.13.1.el9_4 Red Hat Enterprise Linux NFV (v. 9) kernel-rt 5.14.0-427.13.1.el9_4, kernel-rt-kvm 5.14.0-427.13.1.el9_4, kernel-rt-core 5.14.0-427.13.1.el9_4, kernel-rt-modules 5.14.0-427.13.1.el9_4, kernel-rt-debug-kvm 5.14.0-427.13.1.el9_4, kernel-rt-debug-core 5.14.0-427.13.1.el9_4, +6 more Red Hat Enterprise Linux RT (v. 9) kernel-rt 5.14.0-427.13.1.el9_4, kernel-rt-core 5.14.0-427.13.1.el9_4, kernel-rt-modules 5.14.0-427.13.1.el9_4, kernel-rt-debug-core 5.14.0-427.13.1.el9_4, kernel-rt-modules-core 5.14.0-427.13.1.el9_4, kernel-rt-debug-modules 5.14.0-427.13.1.el9_4, +4 more
fixed: vendor fix RHSA-2024:2394
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
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 SSVC

Exploitation: Proof of concept is public
Automatable: no
Technical impact: partial
Assessed: 20 mo ago (2025-02-27)

Exploit prediction

0.27% chance of exploitation in the next 30 days, higher than 19% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

bugzilla.redhat.com https://bugzilla.redhat.com/show_bug.cgi?id=2239848 referenced PoC, tagged "exploit" by a source, unverified
seclists.org https://seclists.org/oss-sec/2023/q3/242 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	3.1	4.4	CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
NVD	3.1	4.7	CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected products

Red Hat Red Hat Enterprise Linux 9
Red Hat Red Hat Enterprise Linux 6
Red Hat Red Hat Enterprise Linux 7
Red Hat Red Hat Enterprise Linux 8

Classification

Weakness

CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization

Technology feeds

Linux kernel rss critical rss

References

access.redhat.com /security/cve/CVE-2023-42756
vdb-entry, patch, third-party-advisory
bugzilla.redhat.com /show_bug.cgi?id=2239848
issue-tracking, exploit, patch, third-party-advisory
seclists.org /oss-sec/2023/q3/242
exploit, mailing-list, patch, third-party-advisory
access.redhat.com /errata/RHSA-2024:2394
vendor-advisory
lists.debian.org /debian-lts-announce/2023/10/msg00027.html
lists.fedoraproject.org /archives/list/package-announce@lists.fedoraproject.org/message/GISYSL3F6WIEVGHJGLC2MFNTUXHPTKQH/
lists.fedoraproject.org /archives/list/package-announce@lists.fedoraproject.org/message/GPMICQ2HVZO5UAM5KPXHAZKA2U3ZDOO6/
lists.fedoraproject.org /archives/list/package-announce@lists.fedoraproject.org/message/V5PDNWPKAP3WL5RQZ4RIDS6MG32OHH5R/

Sources

CVE List CVE-2023-42756
NVD CVE-2023-42756

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.

Summary