Skip to content
Fencer Vulns
high 7.8

CVE-2023-53566 json

netfilter: nft_set_rbtree: fix null deref on element insertion

published 2025-10-04 13 mo ago modified 2026-10-15 24 d ago also EUVD-2025-32293

cvss
7.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 4%
public exploits
0
none known

Summary

In the Linux kernel, the following vulnerability has been resolved:

netfilter: nft_set_rbtree: fix null deref on element insertion

There is no guarantee that rb_prev() will not return NULL in nft_rbtree_gc_elem():

general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f] nft_add_set_elem+0x14b0/0x2990 nf_tables_newsetelem+0x528/0xb30

Furthermore, there is a possible use-after-free while iterating, 'node' can be free'd so we need to cache the next value to use.

Patch / fix

  • Linux Linux 5.10.181, 5.15.113, 6.1.30, 6.3.4, 6.4
  • linux Debian 12 6.1.37-1
  • linux Debian 14, Debian 13 6.3.7-1

debian advisories DEBIAN-CVE-2023-53566

  • linux Ubuntu 22.04 LTS 5.15.0-83.92
  • linux-aws Ubuntu 22.04 LTS 5.15.0-1044.49
  • linux-gcp Ubuntu 22.04 LTS 5.15.0-1041.49
  • linux-gke Ubuntu 22.04 LTS 5.15.0-1041.46
  • linux-ibm Ubuntu 22.04 LTS 5.15.0-1037.40
  • linux-kvm Ubuntu 22.04 LTS 5.15.0-1041.46
  • linux-azure Ubuntu 22.04 LTS 5.15.0-1046.53
  • linux-gkeop Ubuntu 22.04 LTS 5.15.0-1027.32

ubuntu advisories UBUNTU-CVE-2023-53566

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 5.14.0-362.8.1.el9_3
  • rv RHEL 9 5.14.0-362.8.1.el9_3
  • perf RHEL 9 5.14.0-362.8.1.el9_3
  • rtla RHEL 9 5.14.0-362.8.1.el9_3
  • bpftool RHEL 9 7.2.0-362.8.1.el9_3
  • libperf RHEL 9 5.14.0-362.8.1.el9_3
  • kernel-rt RHEL 9 5.14.0-362.8.1.el9_3
  • kernel-64k RHEL 9 5.14.0-362.8.1.el9_3

red hat advisories RHSA-2024:3421RHSA-2023:6583

  • kernel-64kb SLES 15 SP5-LTSS, SLE High Performance Computing 15 SP5-LTSS, SLE High Performance Computing 15 SP5-ESPOS 5.14.21-150500.55.127.1
  • kernel-syms SLES for SAP 15 SP5, SLES 15 SP5-LTSS, SLE High Performance Computing 15 SP5-LTSS +1 more 5.14.21-150500.55.127.1
  • kernel-source SLES for SAP 15 SP5, SLES 15 SP5-LTSS, SLE Micro 5.5 +2 more 5.14.21-150500.55.127.1
  • kernel-default SLES for SAP 15 SP5, SLES 15 SP5-LTSS, SLE Micro 5.5 +3 more 5.14.21-150500.55.127.1
  • kernel-obs-build SLES for SAP 15 SP5, SLES 15 SP5-LTSS, SLE High Performance Computing 15 SP5-LTSS +1 more 5.14.21-150500.55.127.1
  • kernel-default-base SLES for SAP 15 SP5, SLES 15 SP5-LTSS, SLE Micro 5.5 +2 more 5.14.21-150500.55.127.1.150500.6.61.1
  • kernel-64kb SLES 15 SP3-LTSS, SLE High Performance Computing 15 SP3-LTSS, Enterprise Storage 7.1 5.3.18-150300.59.226.2
  • kernel-syms SLES for SAP 15 SP3, SLES 15 SP3-LTSS, SLE High Performance Computing 15 SP3-LTSS +1 more 5.3.18-150300.59.226.1

suse advisories SUSE-SU-2025:4320-1SUSE-SU-2025:4188-1SUSE-SU-2025:4149-1SUSE-SU-2025:4139-1SUSE-SU-2025:4135-1SUSE-SU-2025:4111-1

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-2023-53566 updated cvss 6.4

kernel: netfilter: nft_set_rbtree: fix null deref on element insertion

  • Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 more
    affected: workaround, no fix available “Fix deferred”
  • Red Hat CodeReady Linux Builder EUS (v.9.0) kernel-debuginfo-common-s390x 5.14.0-70.101.1.el9_0, kernel-debuginfo-common-x86_64 5.14.0-70.101.1.el9_0, kernel-debuginfo-common-aarch64 5.14.0-70.101.1.el9_0, kernel-debuginfo-common-ppc64le 5.14.0-70.101.1.el9_0 Red Hat Enterprise Linux AppStream EUS (v.9.0) perf 5.14.0-70.101.1.el9_0, kernel-devel-matched 5.14.0-70.101.1.el9_0, kernel-debug-devel-matched 5.14.0-70.101.1.el9_0, kernel-debuginfo-common-s390x 5.14.0-70.101.1.el9_0, kernel-zfcpdump-devel-matched 5.14.0-70.101.1.el9_0, kernel-debuginfo-common-x86_64 5.14.0-70.101.1.el9_0, +2 more Red Hat Enterprise Linux BaseOS EUS (v.9.0) kernel 5.14.0-70.101.1.el9_0, bpftool 5.14.0-70.101.1.el9_0, kernel-core 5.14.0-70.101.1.el9_0, kernel-tools 5.14.0-70.101.1.el9_0, python3-perf 5.14.0-70.101.1.el9_0, kernel-modules 5.14.0-70.101.1.el9_0, +14 more
    fixed: vendor fix RHSA-2024:3421
  • 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 10 kernel
    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
none
Automatable
no
Technical impact
total
Assessed
24 d ago

Exploit prediction

0.15% chance of exploitation in the next 30 days, higher than 4% 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 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected products

  • Linux Linux

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.