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Back to active CVEs
Medium · CVSS 5.5CVE-2026-23399

nf_tables: nft_dynset: fix possible stateful expression memleak in error pathCVE-2026-23399

Answer in brief

CVE-2026-23399 records a Medium severity (CVSS 5.5) vulnerability in nf_tables: nft_dynset: fix possible stateful expression memleak in error path. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic), Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (generic), Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (generic) and additional mapped packages. Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Mar 28, 2026Updated Oct 15, 2026Source checked Oct 23, 2026First seen by HOL Sep 8, 2026Material review Oct 15, 2026
Upstream Advisory

Key facts

Risk
Medium · CVSS 5.5
Exploitation
Not marked as known exploited
Affected software
18 mapped packages or products
Fix availability
Available

Why this deserves its current priority

CVSS is 5.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Linux/Linux (generic), Linux/Linux (generic), Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (generic), Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (generic) and additional mapped packages. Check affected ranges and fixed versions before updating.

Affected products and reported versions
ProductAffected versionsFixed versions
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*Not reportedNot reported
cpe:2.3:o:linux:linux_kernel:5.11:-:*:*:*:*:*:*Not reportedNot reported
cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*Not reportedNot reported
cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*Not reportedNot reported
cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*Not reportedNot reported
cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:*Not reportedNot reported
cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:*Not reportedNot reported
cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:*Not reportedNot reported
cpe:2.3:o:linux:linux_kernel:7.0:rc7:*:*:*:*:*:*Not reportedNot reported
Mapped affected packages and fixed versions
PackageAffected rangeFixed version
Linux/Linuxgeneric>=563125a73ac30d7036ae69ca35c40500562c1de4 <eb7bf413e59945df03d4567b73ce464eebe2f4ea || >=563125a73ac30d7036ae69ca35c40500562c1de4 <4357dbb1d9c35ca0b4443d71c98a48e6666f7689 || >=563125a73ac30d7036ae69ca35c40500562c1de4 <e6661add2d9c6913e1dad97336595e23a2bed195 || >=563125a73ac30d7036ae69ca35c40500562c1de4 <d1354873cbe3b344899c4311ac05897fd83e3f21 || >=563125a73ac30d7036ae69ca35c40500562c1de4 <31641c682db73353e4647e40735c7f2a75ff58ef || >=563125a73ac30d7036ae69ca35c40500562c1de4 <c88a9fd26cee365bec932196f76175772a941cca || >=563125a73ac30d7036ae69ca35c40500562c1de4 <0548a13b5a145b16e4da0628b5936baf35f51b43eb7bf413e59945df03d4567b73ce464eebe2f4ea, 4357dbb1d9c35ca0b4443d71c98a48e6666f7689, e6661add2d9c6913e1dad97336595e23a2bed195, d1354873cbe3b344899c4311ac05897fd83e3f21, 31641c682db73353e4647e40735c7f2a75ff58ef, c88a9fd26cee365bec932196f76175772a941cca, 0548a13b5a145b16e4da0628b5936baf35f51b43
Linux/Linuxgeneric5.11Not reported
Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFPgeneric>=V3.1.6 <**
Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFPgeneric>=V3.1.7 <**
Siemens/SIMATIC S7-1500 CPU 1518F-4 PN/DP MFPgeneric>=V3.1.6 <**
Siemens/SIMATIC S7-1500 CPU 1518F-4 PN/DP MFPgeneric>=V3.1.7 <**
Siemens/SIMATIC S7-1500 TM MFP - GNU/Linux subsystemgeneric>=0 <**
Siemens/SIPLUS S7-1500 CPU 1518-4 PN/DP MFPgeneric>=V3.1.6 <**
Siemens/SIPLUS S7-1500 CPU 1518-4 PN/DP MFPgeneric>=V3.1.7 <**

Recommended response

  1. 1Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux, Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP.
  2. 2Review the reported fix. Update Linux/Linux to eb7bf413e59945df03d4567b73ce464eebe2f4ea; Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP to *; Siemens/SIMATIC S7-1500 CPU 1518-4 PN/DP MFP to *; Siemens/SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP to *; Siemens/SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP to *; Siemens/SIMATIC S7-1500 TM MFP - GNU/Linux subsystem to *; Siemens/SIPLUS S7-1500 CPU 1518-4 PN/DP MFP to *; Siemens/SIPLUS S7-1500 CPU 1518-4 PN/DP MFP to * if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

  1. Published upstream

    Mar 28, 2026

    Evidence: source:cvelist:source_dates:source-dates:record

  2. Source modified

    Oct 15, 2026

    Evidence: source:cvelist:source_dates:source-dates:record

  3. First seen by HOL

    Sep 8, 2026

Sources and claim methodology

  • Source referencecert-portal.siemens.com
  • Source referencecert-portal.siemens.com
  • Source referencecert-portal.siemens.com
  • Source referencegit.kernel.org
  • Source referencegit.kernel.org
  • Source referencegit.kernel.org
  • Source referencegit.kernel.org
  • Source referencegit.kernel.org
  • Source referencegit.kernel.org
  • Source referencegit.kernel.org
Upstream source description

In the Linux kernel, the following vulnerability has been resolved: nf_tables: nft_dynset: fix possible stateful expression memleak in error path 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

Quoted source text, attributed separately from HOL analysis.

Record context

Vulnerability class
Vulnerability
EPSS
Not reported
CWE IDs
CWE-401
Source
CVE List V5
Source checked
Oct 23, 2026
References
10 linked sources
Open source record