MediumCVE-2026-53219

    Linux Kernel: security vulnerability (CVE-2026-53219)

    Published Last modified Sources: Siemens ProductCERT, SUSE, Debian LTS, Ubuntu, BSI, CVE.org, Msrc Update Guide

    What is affected, what to do

    In the Linux kernel, the following vulnerability has been resolved: netfilter: x_tables: avoid leaking percpu counter pointers The native and compat get-entries paths copy the fixed rule entry header from the kernelized rule blob to userspace before overwriting the entry's counter fields with a sanitized counter snapshot. On SMP kernels, entry->counters.pcnt contains the percpu allocation address used by x_tables rule counters.

    Update Linux Kernel to version 5.10.259, Linux Kernel to version 5.15.210, Linux Kernel to version 6.1.176.

    Affected
    • Linux Kernel lt 4.2..5.10.259
    • Linux Kernel lt 5.11..5.15.210
    • Linux Kernel lt 5.16..6.1.176
    • Linux Kernel lt 6.2..6.6.143
    • Linux Kernel lt 6.7..6.12.94
    • Linux Kernel lt 6.13..6.18.36
    • Linux Kernel lt 6.19..7.0.13
    Fixed in
    • Linux Kernel 5.10.259
    • Linux Kernel 5.15.210
    • Linux Kernel 6.1.176
    • Linux Kernel 6.6.143
    • Linux Kernel 6.12.94
    • Linux Kernel 6.18.36
    • Linux Kernel 7.0.13
    • Linux Kernel 7.1

    Not sure whether and how you are affected? Ask a question about this vulnerability

    Metrics

    5.5

    Priority

    XIEM Effective CVSS: highest available CVSS rating from NVD and vendor data.

    Source: NVD, CVSS v3

    5.5

    CVSS v3

    Severity Medium on the scale from 0 to 10.

    Source: Siemens ProductCERT, SUSE, Debian LTS, Ubuntu, BSI, CVE.org, Msrc Update Guide

    0.1 %

    EPSS score

    Low — model estimates < 1% exploitation likelihood.

    Source: FIRST EPSS, percentile 2.5

    Show all metrics
    Severity
    Medium
    Priority (0–325)

    The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first?

    Read in glossary
    47.07 Methodology
    Exploit maturity

    An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack.

    Read in glossary
    no public PoC known
    XIEM Effective CVSS

    XIEM® is the tiered managed-security operating model from NEOSEC and a registered trademark of NEOSEC GmbH. It extends classic SIEM — the central collection, normalisation and correlation of security-relevant events — with endpoint forensics, network visibility and deception technology, and consolidates them into three building tiers: Sentry, Orchestrate and Command.

    Read in glossary
    5.5 Methodology
    CVSS v3

    CVSS is the globally established, open standard for assessing the technical severity of a vulnerability on a scale from 0 to 10. It describes how easily a flaw can be exploited and what damage it can cause — but not how likely its actual exploitation is. CVSS and the complementary EPSS deliberately answer different questions.

    Read in glossary
    5.5
    EPSS score

    The EPSS score is the absolute model output for an individual vulnerability: the estimated probability of real-world exploitation within the next 30 days, expressed as a value between 0 and 1 (i.e. 0 % to 100 %). A score of 0.42 means „the model estimates a 42 % chance of real-world exploitation within 30 days“.

    Read in glossary
    0.1 %
    Low — model estimates < 1% exploitation likelihood.
    EPSS percentile

    The EPSS percentile is the relative position of a vulnerability within all EPSS-scored CVEs, expressed as a value between 0 and 1. A percentile of 0.90 means „this CVE has a higher EPSS score than 90 % of all other scored CVEs“. Unlike the EPSS score, it is not a probability — but a positioning within a ranking.

    Read in glossary
    2.5
    Low — this CVE sits in the lower 10% of all CVEs scored today.
    KEV status

    The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching.

    Read in glossary
    —
    Published

    Detection rules

    No NEOSEC detection rule is available for this vulnerability yet.

    Classification under NIS2 and CRA

    Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.

    NIS2

    NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management.

    Read in glossary
    Handle the vulnerability in regular vulnerability handling under Art. 21(2)(e) NIS2.
    CRA

    The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates.

    Read in glossary
    From 11.12.2027, Annex I Part II CRA requires manufacturers of affected products with digital elements to handle vulnerabilities without delay and provide security updates.
    ISO/IEC 27001

    ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security.

    Read in glossary
    Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.

    Description

    In the Linux kernel, the following vulnerability has been resolved: netfilter: x_tables: avoid leaking percpu counter pointers The native and compat get-entries paths copy the fixed rule entry header from the kernelized rule blob to userspace before overwriting the entry's counter fields with a sanitized counter snapshot. On SMP kernels, entry->counters.pcnt contains the percpu allocation address used by x_tables rule counters. A caller can provide a userspace buffer that faults during the initial fixed-header copy after pcnt has been copied but before the later sanitized counter copy runs. The syscall then returns -EFAULT while leaving the raw percpu pointer in userspace. Copy only the fixed entry prefix before counters from the kernelized rule blob, then copy the sanitized counter snapshot into the counter field. Apply this ordering to the IPv4, IPv6, and ARP native and compat get-entries implementations so a fault cannot expose the internal percpu counter pointer.

    Source: siemens_advisory, suse_csaf, Debian LTS Advisories, Ubuntu Security Notices, BSI WID Portal, BSI CSAF, NVD (NIST), CVE.org (MITRE), cvelistv5, Microsoft Security Update Guide

    Affected products

    The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.

    Affected products
    Affected versionsFixed in
    LinuxLinux
    • 4.2 – < 5.10.259
    • 6.7 – < 6.12.94
    • 6.13 – < 6.18.36
    • 5.11 – < 5.15.210
    • —
    • 5.16 – < 6.1.176
    • 6.19 – < 7.0.13
    • 6.2 – < 6.6.143
    • 5.10.259
    • 6.12.94
    • 6.18.36
    • 5.15.210
    • 7.1
    • 6.1.176
    • 7.0.13
    • 6.6.143
    SiemensSIMATIC S7
    • 1500 TM MFP V1.1.1 GNU/Linux subsystem
    • —

    Vendors and products

    Affected operating systems

    Affected operating systems
    Linuxdebianlinuxbookworm
    Linuxdebianlinuxbullseye
    Linuxdebianlinux-6.1bullseye
    Linuxubuntulinux-oracle-7.0noble
    Linuxlinuxlinux_kernel7.1
    Linuxlinuxlinux_kernel—

    References & sources

    Changes to this CVE

    Who changed this CVE and when: NVD (analysis, affected products, CVSS), the CVE publisher (CNA) and additional providers such as CISA (ADP).

    1. Record modifiedSiemens ADP

      Show 3 original changes
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Affected versions (publisher)added
      —
      Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/53xxx/CVE-2026-53219.json">CVE-2026-53219</a>
      Referenceadded
      —
      https://cert-portal.siemens.com/productcert/html/ssa-457936.html
      Referenceadded
      —
      https://cert-portal.siemens.com/productcert/html/ssa-784472.html

      Source identifier: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e

    2. Record modifiedLinux

      Show 24 original changes
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Referenceadded
      —
      https://git.kernel.org/stable/c/08a3e218064db11f154ad9ad5541751ea7f34ebe
      Referenceadded
      —
      https://git.kernel.org/stable/c/0b35dc8527ccc16b7dc34e8a3164313e68cd4e45
      Referenceadded
      —
      https://git.kernel.org/stable/c/8d67e42ad3b1a95a152541015a07110e06992d6c
      Referenceadded
      —
      https://git.kernel.org/stable/c/a0d16941adf3a501956d74aefd8d6e217906e79c
      Referenceadded
      —
      https://git.kernel.org/stable/c/b28e2fcad3db7e8687b15bc20bced26b5b7c920e
      Referenceadded
      —
      https://git.kernel.org/stable/c/b74ba3343eb44b2cbf7e9665918c287df1d52ebb
      Referenceadded
      —
      https://git.kernel.org/stable/c/f7f2fbb0e893a0238dc464f8d8c0f5609bec584f
      Referenceadded
      —
      https://git.kernel.org/stable/c/fb0521aff1e10e300d89725cc439d3ea74c828c5
      Referenceremoved
      https://git.kernel.org/stable/c/08a3e218064db11f154ad9ad5541751ea7f34ebe
      —
      Referenceremoved
      https://git.kernel.org/stable/c/0b35dc8527ccc16b7dc34e8a3164313e68cd4e45
      —
      Referenceremoved
      https://git.kernel.org/stable/c/8d67e42ad3b1a95a152541015a07110e06992d6c
      —
      Referenceremoved
      https://git.kernel.org/stable/c/a0d16941adf3a501956d74aefd8d6e217906e79c
      —
      Referenceremoved
      https://git.kernel.org/stable/c/b28e2fcad3db7e8687b15bc20bced26b5b7c920e
      —
      Referenceremoved
      https://git.kernel.org/stable/c/b74ba3343eb44b2cbf7e9665918c287df1d52ebb
      —
      Referenceremoved
      https://git.kernel.org/stable/c/f7f2fbb0e893a0238dc464f8d8c0f5609bec584f
      —
      Referenceremoved
      https://git.kernel.org/stable/c/fb0521aff1e10e300d89725cc439d3ea74c828c5
      —
      Reference typeremoved
      https://git.kernel.org/stable/c/08a3e218064db11f154ad9ad5541751ea7f34ebe Types: Patch
      —
      Reference typeremoved
      https://git.kernel.org/stable/c/0b35dc8527ccc16b7dc34e8a3164313e68cd4e45 Types: Patch
      —
      Reference typeremoved
      https://git.kernel.org/stable/c/8d67e42ad3b1a95a152541015a07110e06992d6c Types: Patch
      —
      Reference typeremoved
      https://git.kernel.org/stable/c/a0d16941adf3a501956d74aefd8d6e217906e79c Types: Patch
      —
      Reference typeremoved
      https://git.kernel.org/stable/c/b28e2fcad3db7e8687b15bc20bced26b5b7c920e Types: Patch
      —
      Reference typeremoved
      https://git.kernel.org/stable/c/b74ba3343eb44b2cbf7e9665918c287df1d52ebb Types: Patch
      —
      Reference typeremoved
      https://git.kernel.org/stable/c/f7f2fbb0e893a0238dc464f8d8c0f5609bec584f Types: Patch
      —
      Reference typeremoved
      https://git.kernel.org/stable/c/fb0521aff1e10e300d89725cc439d3ea74c828c5 Types: Patch
      —

      Source identifier: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    3. Record modifiedSiemens ADP

      Show 2 original changes
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Affected versions (publisher)added
      —
      New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/53xxx/CVE-2026-53219.json">CVE-2026-53219</a>
      Referenceadded
      —
      https://cert-portal.siemens.com/productcert/html/ssa-019113.html

      Source identifier: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e

    4. Initial analysis by NVDNVD

      Newly listed as affected:
      • Linux Kernel (5.16 – before 6.1.176; 6.2 – before 6.6.143; 5.11 – before 5.15.210; 6.13 – before 6.18.36; 6.7 – before 6.12.94; 6.19 – before 7.0.13; 4.2 – before 5.10.259; 7 individual versions)

      CVSS V3.1: AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

      Show 11 original changes
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      CVSSadded
      —
      AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
      Weakness type (CWE)added
      —
      NVD-CWE-noinfo
      Product configurationadded
      —
      OR *cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.16 up to (excluding) 6.1.176 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.2 up to (excluding) 6.6.143 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.11 up to (excluding) 5.15.210 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.13 up to (excluding) 6.18.36 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.7 up to (excluding) 6.12.94 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.19 up to (excluding) 7.0.13 *cpe:2.3:o:linux:linux_kernel:7.1:rc5:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.1:rc6:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.1:rc7:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 4.2 up to (excluding) 5.10.259
      Reference typeadded
      —
      kernel.org: https://git.kernel.org/stable/c/08a3e218064db11f154ad9ad5541751ea7f34ebe Types: Patch
      Reference typeadded
      —
      kernel.org: https://git.kernel.org/stable/c/0b35dc8527ccc16b7dc34e8a3164313e68cd4e45 Types: Patch
      Reference typeadded
      —
      kernel.org: https://git.kernel.org/stable/c/8d67e42ad3b1a95a152541015a07110e06992d6c Types: Patch
      Reference typeadded
      —
      kernel.org: https://git.kernel.org/stable/c/a0d16941adf3a501956d74aefd8d6e217906e79c Types: Patch
      Reference typeadded
      —
      kernel.org: https://git.kernel.org/stable/c/b28e2fcad3db7e8687b15bc20bced26b5b7c920e Types: Patch
      Reference typeadded
      —
      kernel.org: https://git.kernel.org/stable/c/b74ba3343eb44b2cbf7e9665918c287df1d52ebb Types: Patch
      Reference typeadded
      —
      kernel.org: https://git.kernel.org/stable/c/f7f2fbb0e893a0238dc464f8d8c0f5609bec584f Types: Patch
      Reference typeadded
      —
      kernel.org: https://git.kernel.org/stable/c/fb0521aff1e10e300d89725cc439d3ea74c828c5 Types: Patch

      Source identifier: nvd@nist.gov

    Embed badge

    Show the severity and KEV status of this vulnerability on your site – with a link back here. The image is updated hourly.

    Badge preview for CVE-2026-53219
    <a href="https://intel.neosec.eu/en/cve/CVE-2026-53219"><img src="https://intel.neosec.eu/badge/cve/CVE-2026-53219.svg?lang=en" alt="CVE-2026-53219 – NEOSEC Intel" height="20"></a>