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Fencer Vulns
high 7.8

CVE-2023-31248 json

Linux Kernel nftables Use-After-Free Local Privilege Escalation Vulnerability

published 2023-07-05 3 y ago modified 2026-06-17 4 mo ago also EUVD-2023-35563

cvss
7.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
1.9%
EPSS 1.9% chance of exploitation in 30 days, percentile 79%
public exploits
0
none known

Summary

Linux Kernel nftables Use-After-Free Local Privilege Escalation Vulnerability; `nft_chain_lookup_byid()` failed to check whether a chain was active and CAP_NET_ADMIN is in any user or network namespace

Patch / fix

  • linux linux_kernel 5.10.188, 5.15.121, 6.1.39, 6.4.4
  • linux Debian 12 6.1.38-1
  • linux Debian 14, Debian 13 6.4.4-1

debian advisories DEBIAN-CVE-2023-31248

  • 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-2023-31248

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

  • kpatch-patch-5_14_0-284_11_1 RHEL 9 1-5.el9_2
  • kpatch-patch-5_14_0-284_18_1 RHEL 9 1-4.el9_2
  • kpatch-patch-5_14_0-284_25_1 RHEL 9 1-3.el9_2
  • kernel RHEL 9 5.14.0-284.30.1.el9_2
  • perf RHEL 9 5.14.0-284.30.1.el9_2
  • rtla RHEL 9 5.14.0-284.30.1.el9_2
  • bpftool RHEL 9 7.0.0-284.30.1.el9_2
  • kernel-64k RHEL 9 5.14.0-284.30.1.el9_2

red hat advisories RHSA-2023:5604RHSA-2023:5603RHSA-2023:5575RHSA-2023:5093RHSA-2023:5069RHSA-2023:5091

  • kernel-rt Real Time Module 15 SP7 6.4.0-150700.7.22.1
  • kernel-syms-rt Real Time Module 15 SP7 6.4.0-150700.7.22.1
  • kernel-source-rt Real Time Module 15 SP7 6.4.0-150700.7.22.1
  • kernel-azure SLE Module for Public Cloud 15 SP7 6.4.0-150700.20.18.1
  • kernel-syms-azure SLE Module for Public Cloud 15 SP7 6.4.0-150700.20.18.1
  • kernel-source-azure SLE Module for Public Cloud 15 SP7 6.4.0-150700.20.18.1
  • kernel-64kb SLE Module for Basesystem 15 SP7 6.4.0-150700.53.22.1
  • kernel-syms SLE Module for Development Tools 15 SP7 6.4.0-150700.53.22.1

suse advisories SUSE-SU-2025:4141-1SUSE-SU-2025:4132-1SUSE-SU-2025:4057-1SUSE-SU-2025:20870-1SUSE-SU-2025:3761-1SUSE-SU-2025:20898-1

  • kernel AlmaLinux 9 5.14.0-284.30.1.el9_2
  • perf AlmaLinux 9 5.14.0-284.30.1.el9_2
  • rtla AlmaLinux 9 5.14.0-284.30.1.el9_2
  • bpftool AlmaLinux 9 7.0.0-284.30.1.el9_2
  • kernel-64k AlmaLinux 9 5.14.0-284.30.1.el9_2
  • kernel-core AlmaLinux 9 5.14.0-284.30.1.el9_2
  • kernel-tools AlmaLinux 9 5.14.0-284.30.1.el9_2
  • python3-perf AlmaLinux 9 5.14.0-284.30.1.el9_2

almalinux advisories ALSA-2023:5069ALSA-2023:5091

  • kernel-rt Rocky Linux 9 5.14.0-284.30.1.rt14.315.el9_2

rocky linux advisories RLSA-2023:5091

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-2023-31248 updated cvss 7.8

kernel: nf_tables: use-after-free in nft_chain_lookup_byid()

  • Red Hat CodeReady Linux Builder EUS (v.9.0) kernel-debuginfo-common-s390x 5.14.0-70.75.1.el9_0, kernel-debuginfo-common-x86_64 5.14.0-70.75.1.el9_0, kernel-debuginfo-common-aarch64 5.14.0-70.75.1.el9_0, kernel-debuginfo-common-ppc64le 5.14.0-70.75.1.el9_0
    fixed: vendor fix RHSA-2023:5604
  • Red Hat Enterprise Linux AppStream (v. 9) perf 5.14.0-284.30.1.el9_2, rtla 5.14.0-284.30.1.el9_2, kernel-devel-matched 5.14.0-284.30.1.el9_2, kernel-64k-devel-matched 5.14.0-284.30.1.el9_2, kernel-debug-devel-matched 5.14.0-284.30.1.el9_2, kernel-debuginfo-common-s390x 5.14.0-284.30.1.el9_2, +5 more
    fixed: vendor fix RHSA-2023:5069
  • Red Hat Enterprise Linux AppStream EUS (v.9.0) perf 5.14.0-70.75.1.el9_0, kernel-devel-matched 5.14.0-70.75.1.el9_0, kernel-debug-devel-matched 5.14.0-70.75.1.el9_0, kernel-debuginfo-common-s390x 5.14.0-70.75.1.el9_0, kernel-zfcpdump-devel-matched 5.14.0-70.75.1.el9_0, kernel-debuginfo-common-x86_64 5.14.0-70.75.1.el9_0, +2 more
    fixed: vendor fix RHSA-2023:5604
  • Red Hat Enterprise Linux BaseOS (v. 9) bpftool 7.0.0-284.30.1.el9_2, kernel 5.14.0-284.30.1.el9_2, kernel-64k 5.14.0-284.30.1.el9_2, kernel-core 5.14.0-284.30.1.el9_2, kernel-tools 5.14.0-284.30.1.el9_2, python3-perf 5.14.0-284.30.1.el9_2, +31 more
    fixed: vendor fix RHSA-2023:5069
  • Red Hat Enterprise Linux BaseOS EUS (v.9.0) kernel 5.14.0-70.75.1.el9_0, bpftool 5.14.0-70.75.1.el9_0, kernel-core 5.14.0-70.75.1.el9_0, kernel-tools 5.14.0-70.75.1.el9_0, python3-perf 5.14.0-70.75.1.el9_0, kernel-modules 5.14.0-70.75.1.el9_0, +20 more
    fixed: vendor fix RHSA-2023:5604
  • Red Hat Enterprise Linux CRB (v. 9) kernel-debuginfo-common-s390x 5.14.0-284.30.1.el9_2, kernel-debuginfo-common-x86_64 5.14.0-284.30.1.el9_2, kernel-debuginfo-common-aarch64 5.14.0-284.30.1.el9_2, kernel-debuginfo-common-ppc64le 5.14.0-284.30.1.el9_2
    fixed: vendor fix RHSA-2023:5069
  • Red Hat Enterprise Linux NFV (v. 9) kernel-rt 5.14.0-284.30.1.rt14.315.el9_2, kernel-rt-kvm 5.14.0-284.30.1.rt14.315.el9_2, kernel-rt-core 5.14.0-284.30.1.rt14.315.el9_2, kernel-rt-modules 5.14.0-284.30.1.rt14.315.el9_2, kernel-rt-debug-kvm 5.14.0-284.30.1.rt14.315.el9_2, kernel-rt-debug-core 5.14.0-284.30.1.rt14.315.el9_2, +6 more
    fixed: vendor fix RHSA-2023:5091
  • Red Hat Enterprise Linux Real Time EUS (v.9.0) kernel-rt 5.14.0-70.75.1.rt21.146.el9_0, kernel-rt-core 5.14.0-70.75.1.rt21.146.el9_0, kernel-rt-modules 5.14.0-70.75.1.rt21.146.el9_0, kernel-rt-debug-core 5.14.0-70.75.1.rt21.146.el9_0, kernel-rt-debug-modules 5.14.0-70.75.1.rt21.146.el9_0, kernel-rt-modules-extra 5.14.0-70.75.1.rt21.146.el9_0, +2 more Red Hat Enterprise Linux Real Time for NFV EUS (v.9.0) kernel-rt 5.14.0-70.75.1.rt21.146.el9_0, kernel-rt-kvm 5.14.0-70.75.1.rt21.146.el9_0, kernel-rt-core 5.14.0-70.75.1.rt21.146.el9_0, kernel-rt-modules 5.14.0-70.75.1.rt21.146.el9_0, kernel-rt-debug-kvm 5.14.0-70.75.1.rt21.146.el9_0, kernel-rt-debug-core 5.14.0-70.75.1.rt21.146.el9_0, +4 more
    fixed: vendor fix RHSA-2023:5603
show 2 more
  • Red Hat Enterprise Linux RT (v. 9) kernel-rt 5.14.0-284.30.1.rt14.315.el9_2, kernel-rt-core 5.14.0-284.30.1.rt14.315.el9_2, kernel-rt-modules 5.14.0-284.30.1.rt14.315.el9_2, kernel-rt-debug-core 5.14.0-284.30.1.rt14.315.el9_2, kernel-rt-modules-core 5.14.0-284.30.1.rt14.315.el9_2, kernel-rt-debug-modules 5.14.0-284.30.1.rt14.315.el9_2, +4 more
    fixed: vendor fix RHSA-2023:5091
  • 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 AppStream (v. 9) kernel-doc 5.14.0-284.30.1.el9_2
    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-23-166-10 updated cvss 7.8

Siemens SIMATIC S7-1500 TM MFP BIOS

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

1.89% chance of exploitation in the next 30 days, higher than 79% 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 Linux Kernel

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.