HighCVE-2026-46234

    Linux Kernel: security vulnerability (CVE-2026-46234)

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

    What is affected, what to do

    In the Linux kernel, the following vulnerability has been resolved: vsock: fix buffer size clamping order In vsock_update_buffer_size(), the buffer size was being clamped to the maximum first, and then to the minimum. If a user sets a minimum buffer size larger than the maximum, the minimum check overrides the maximum check, inverting the constraint.

    Update Linux Kernel to version 5.10.258, Linux Kernel to version 5.15.209, Linux Kernel to version 6.1.175.

    Affected
    • Linux Kernel lt 5.5..5.10.258
    • Linux Kernel lt 5.11..5.15.209
    • Linux Kernel lt 5.16..6.1.175
    • Linux Kernel lt 6.2..6.6.140
    • Linux Kernel lt 6.7..6.12.90
    • Linux Kernel lt 6.13..6.18.32
    • Linux Kernel lt 6.19..7.0.9
    Fixed in
    • Linux Kernel 5.10.258
    • Linux Kernel 5.15.209
    • Linux Kernel 6.1.175
    • Linux Kernel 6.6.140
    • Linux Kernel 6.12.90
    • Linux Kernel 6.18.32
    • Linux Kernel 7.0.9
    • Linux Kernel 7.1

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

    Metrics

    7.8

    Priority

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

    Source: NVD, CVSS v3

    7.8

    CVSS v3

    Severity High on the scale from 0 to 10.

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

    0.1 %

    EPSS score

    Low — model estimates < 1% exploitation likelihood.

    Source: FIRST EPSS, percentile 2.7

    Show all metrics
    Severity
    High
    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
    57.11 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
    7.8 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
    7.8
    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
    2.7
    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
    High technical severity: assess and remediate the vulnerability in vulnerability handling under Art. 21(2)(e) NIS2 and document the decision.
    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: vsock: fix buffer size clamping order In vsock_update_buffer_size(), the buffer size was being clamped to the maximum first, and then to the minimum. If a user sets a minimum buffer size larger than the maximum, the minimum check overrides the maximum check, inverting the constraint. This breaks the intended socket memory boundaries by allowing the vsk->buffer_size to grow beyond the configured vsk->buffer_max_size. Fix this by checking the minimum first, and then the maximum. This ensures the buffer size never exceeds the buffer_max_size.

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

    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
    • 5.16 – < 6.1.175
    • 5.5 – < 5.10.258
    • 6.2 – < 6.6.140
    • 6.19 – < 7.0.9
    • 6.13 – < 6.18.32
    • 5.11 – < 5.15.209
    • —
    • 6.7 – < 6.12.90
    • 6.1.175
    • 5.10.258
    • 6.6.140
    • 7.0.9
    • 6.18.32
    • 5.15.209
    • 7.1
    • 6.12.90
    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_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 modifiedLinux

      Show 24 original changes
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Referenceadded
      —
      https://git.kernel.org/stable/c/01ef69785dc3162f588a361ab770b1e312800188
      Referenceadded
      —
      https://git.kernel.org/stable/c/0b68881501460c3761f196469e1e503218c5e536
      Referenceadded
      —
      https://git.kernel.org/stable/c/2602f7bb5818e92315feeaeb71d8ce4d5c9ab160
      Referenceadded
      —
      https://git.kernel.org/stable/c/310da27932dd0afe7ce7456dfe1f0814c3301f41
      Referenceadded
      —
      https://git.kernel.org/stable/c/a998a7e250bf976539e05a00ec64a81292afecaa
      Referenceadded
      —
      https://git.kernel.org/stable/c/caf11dfea5233a69298a1c448bbf8d1639c80536
      Referenceadded
      —
      https://git.kernel.org/stable/c/d114bfdc9b76bf93b881e195b7ec957c14227bab
      Referenceadded
      —
      https://git.kernel.org/stable/c/f6ec135941d2c1c2dbb87b5ce1783f4f6ac6ccca
      Referenceremoved
      https://git.kernel.org/stable/c/01ef69785dc3162f588a361ab770b1e312800188
      —
      Referenceremoved
      https://git.kernel.org/stable/c/0b68881501460c3761f196469e1e503218c5e536
      —
      Referenceremoved
      https://git.kernel.org/stable/c/2602f7bb5818e92315feeaeb71d8ce4d5c9ab160
      —
      Referenceremoved
      https://git.kernel.org/stable/c/310da27932dd0afe7ce7456dfe1f0814c3301f41
      —
      Referenceremoved
      https://git.kernel.org/stable/c/a998a7e250bf976539e05a00ec64a81292afecaa
      —
      Referenceremoved
      https://git.kernel.org/stable/c/caf11dfea5233a69298a1c448bbf8d1639c80536
      —
      Referenceremoved
      https://git.kernel.org/stable/c/d114bfdc9b76bf93b881e195b7ec957c14227bab
      —
      Referenceremoved
      https://git.kernel.org/stable/c/f6ec135941d2c1c2dbb87b5ce1783f4f6ac6ccca
      —
      Reference typeremoved
      https://git.kernel.org/stable/c/01ef69785dc3162f588a361ab770b1e312800188 Types: Patch
      —
      Reference typeremoved
      https://git.kernel.org/stable/c/0b68881501460c3761f196469e1e503218c5e536 Types: Patch
      —
      Reference typeremoved
      https://git.kernel.org/stable/c/2602f7bb5818e92315feeaeb71d8ce4d5c9ab160 Types: Patch
      —
      Reference typeremoved
      https://git.kernel.org/stable/c/310da27932dd0afe7ce7456dfe1f0814c3301f41 Types: Patch
      —
      Reference typeremoved
      https://git.kernel.org/stable/c/a998a7e250bf976539e05a00ec64a81292afecaa Types: Patch
      —
      Reference typeremoved
      https://git.kernel.org/stable/c/caf11dfea5233a69298a1c448bbf8d1639c80536 Types: Patch
      —
      Reference typeremoved
      https://git.kernel.org/stable/c/d114bfdc9b76bf93b881e195b7ec957c14227bab Types: Patch
      —
      Reference typeremoved
      https://git.kernel.org/stable/c/f6ec135941d2c1c2dbb87b5ce1783f4f6ac6ccca Types: Patch
      —

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

    2. 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/2026/46xxx/CVE-2026-46234.json">CVE-2026-46234</a>
      Referenceadded
      —
      https://cert-portal.siemens.com/productcert/html/ssa-784472.html

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

    3. Initial analysis by NVDNVD

      Newly listed as affected:
      • Linux Kernel (5.16 – before 6.1.175; 5.11 – before 5.15.209; 6.2 – before 6.6.140; 6.13 – before 6.18.32; 6.7 – before 6.12.90; 6.19 – before 7.0.9; 5.5 – before 5.10.258)

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

      Weakness type: CWE-787

      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:H/I:H/A:H
      Weakness type (CWE)added
      —
      CWE-787
      Product configurationadded
      —
      OR *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.16 up to (excluding) 6.1.175 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.11 up to (excluding) 5.15.209 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.2 up to (excluding) 6.6.140 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.13 up to (excluding) 6.18.32 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.7 up to (excluding) 6.12.90 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.19 up to (excluding) 7.0.9 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.5 up to (excluding) 5.10.258
      Reference typeadded
      —
      kernel.org: https://git.kernel.org/stable/c/01ef69785dc3162f588a361ab770b1e312800188 Types: Patch
      Reference typeadded
      —
      kernel.org: https://git.kernel.org/stable/c/0b68881501460c3761f196469e1e503218c5e536 Types: Patch
      Reference typeadded
      —
      kernel.org: https://git.kernel.org/stable/c/2602f7bb5818e92315feeaeb71d8ce4d5c9ab160 Types: Patch
      Reference typeadded
      —
      kernel.org: https://git.kernel.org/stable/c/310da27932dd0afe7ce7456dfe1f0814c3301f41 Types: Patch
      Reference typeadded
      —
      kernel.org: https://git.kernel.org/stable/c/a998a7e250bf976539e05a00ec64a81292afecaa Types: Patch
      Reference typeadded
      —
      kernel.org: https://git.kernel.org/stable/c/caf11dfea5233a69298a1c448bbf8d1639c80536 Types: Patch
      Reference typeadded
      —
      kernel.org: https://git.kernel.org/stable/c/d114bfdc9b76bf93b881e195b7ec957c14227bab Types: Patch
      Reference typeadded
      —
      kernel.org: https://git.kernel.org/stable/c/f6ec135941d2c1c2dbb87b5ce1783f4f6ac6ccca Types: Patch

      Source identifier: nvd@nist.gov

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