medium 5.5

CVE-2026-23399 json

nf_tables: nft_dynset: fix possible stateful expression memleak in error path

published 2026-03-28 7mo ago modified 2026-11-05 4d ago also EUVD-2026-16909

cvss: 5.5; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 0.1%; EPSS 0.1% chance of exploitation in 30 days, percentile 2%
public exploits: 0; none known

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

If cloning the second stateful expression in the element via GFP_ATOMIC fails, then the first stateful expression remains in place without being released.

unreferenced object (percpu) 0x607b97e9cab8 (size 16): comm "softirq", pid 0, jiffies 4294931867 hex dump (first 16 bytes on cpu 3): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 backtrace (crc 0): pcpu_alloc_noprof+0x453/0xd80 nft_counter_clone+0x9c/0x190 [nf_tables] nft_expr_clone+0x8f/0x1b0 [nf_tables] nft_dynset_new+0x2cb/0x5f0 [nf_tables] nft_rhash_update+0x236/0x11c0 [nf_tables] nft_dynset_eval+0x11f/0x670 [nf_tables] nft_do_chain+0x253/0x1700 [nf_tables] nft_do_chain_ipv4+0x18d/0x270 [nf_tables] nf_hook_slow+0xaa/0x1e0 ip_local_deliver+0x209/0x330

Patch / fix

fixed in 1 distros 4 links 7

Linux Linux 5.15.209, 6.1.175, 6.6.136, 6.12.78, 6.18.20, 6.19.10, 7.0

debian ubuntu suse azure linux

linux Debian 12 6.1.176-1
linux Debian 13 6.12.85-1
linux Debian 14 6.19.10-1

debian advisories DEBIAN-CVE-2026-23399

linux Ubuntu 22.04 LTS 5.15.0-186.196
linux Ubuntu 24.04 LTS 6.8.0-136.136
linux-aws Ubuntu 22.04 LTS 5.15.0-1112.119
linux-aws Ubuntu 24.04 LTS 6.8.0-1061.64
linux-gcp Ubuntu 22.04 LTS 5.15.0-1112.122
linux-gcp Ubuntu 24.04 LTS 6.8.0-1064.72
linux-gke Ubuntu 22.04 LTS 5.15.0-1108.114
linux-gke Ubuntu 24.04 LTS 6.8.0-1059.67

ubuntu advisories UBUNTU-CVE-2026-23399

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-64kb SLE Module for Basesystem 15 SP7 6.4.0-150700.53.55.1
kernel-syms SLE Module for Development Tools 15 SP7 6.4.0-150700.53.55.1
kernel-azure SLE Module for Public Cloud 15 SP7 6.4.0-150700.53.55.1
kernel-source SLE Module for Development Tools 15 SP7, SLE Module for Basesystem 15 SP7 6.4.0-150700.53.55.1
kernel-default SLE Workstation Extension 15 SP7, SLE Module for Legacy 15 SP7, SLE Module for Basesystem 15 SP7 +2 more 6.4.0-150700.53.55.1
kernel-zfcpdump SLE Module for Basesystem 15 SP7 6.4.0-150700.53.55.1
kernel-obs-build SLE Module for Development Tools 15 SP7 6.4.0-150700.53.55.1
kernel-default-base SLE Module for Basesystem 15 SP7 6.4.0-150700.53.55.1.150700.17.33.1

suse advisories SUSE-SU-2026:2238-1 SUSE-SU-2026:21834-1

kernel Azure Linux 3.0 6.6.137.1-2

azure linux advisories AZL-81017

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

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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-2026-23399 updated 2026-11-07 cvss 5.5

kernel: nf_tables: nft_dynset: fix possible stateful expression memleak in error path

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 Red Hat Enterprise Linux 10 kernel
affected: no fix available “Fix deferred”
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
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-26-295-11 updated 2026-10-22 cvss 0.0

Siemens SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP

Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0) >= 3.1.7 Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0) >= 3.1.7 Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0) >= 3.1.7 Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0) >= 3.1.7 Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0) >= 3.1.7
affected: mitigation, no fix available

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

cisa ICSA-26-295-16 updated 2026-10-22 cvss 0.0

Siemens SIMATIC S7-1500 TM MFP

Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem
affected: mitigation, no fix available

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: partial
Assessed: 4d ago (2026-11-05)

Exploit prediction

0.13% chance of exploitation in the next 30 days, higher than 2% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
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
Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP
Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP
Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem
Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP

Classification

Weakness

CWE-401 Missing Release of Memory after Effective Lifetime

Technology feeds

Linux kernel rss critical rss

References

Sources

CVE List CVE-2026-23399
NVD CVE-2026-23399

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