LowCVE-2026-74719

    Linux Kernel: security vulnerability (CVE-2026-74719)

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

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    What is affected, what to do

    In the Linux kernel, the following vulnerability has been resolved: net/smc: fix qentry overwrite for CONFIRM_LINK and ADD_LINK_CONT in smc_llc_event_handler() The SMC_LLC_CONFIRM_LINK / SMC_LLC_ADD_LINK_CONT branch in smc_llc_event_handler() stores an incoming qentry into the local LLC flow without first checking whether a qentry is already pending. If a malicious or buggy peer sends a second CONFIRM_LINK or ADD_LINK_CONT request while a flow is active and flow->qentry is already set, smc_llc_flow_qentry_set() overwrites the pointer without freeing the previous allocation, leaking one kmalloc-96 object per spurious message.

    Update Linux Kernel to version 5.10.265, Linux Kernel to version 5.15.216, Linux Kernel to version 6.1.183.

    Affected
    • Linux Kernel lt 5.8..5.10.265
    • Linux Kernel lt 5.11..5.15.216
    • Linux Kernel lt 5.16..6.1.183
    • Linux Kernel lt 6.2..6.6.152
    • Linux Kernel lt 6.7..6.12.104
    • Linux Kernel lt 6.13..6.18.45
    • Linux Kernel lt 6.19..7.1.9
    Fixed in
    • Linux Kernel 5.10.265
    • Linux Kernel 5.15.216
    • Linux Kernel 6.1.183
    • Linux Kernel 6.6.152
    • Linux Kernel 6.12.104
    • Linux Kernel 6.18.45
    • Linux Kernel 7.1.9
    • Linux Kernel 7.2

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

    Metrics

    3.7

    Priority

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

    Source: Vendor (CNA), CVSS v3

    3.7

    CVSS v3

    Severity Low on the scale from 0 to 10.

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

    0.2 %

    EPSS score

    Low — model estimates < 1% exploitation likelihood.

    Source: FIRST EPSS, percentile 7.3

    Show all metrics
    Severity
    Low
    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
    42.13 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
    3.7 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
    3.7
    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
    0.2 %
    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
    7.3
    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: net/smc: fix qentry overwrite for CONFIRM_LINK and ADD_LINK_CONT in smc_llc_event_handler() The SMC_LLC_CONFIRM_LINK / SMC_LLC_ADD_LINK_CONT branch in smc_llc_event_handler() stores an incoming qentry into the local LLC flow without first checking whether a qentry is already pending. If a malicious or buggy peer sends a second CONFIRM_LINK or ADD_LINK_CONT request while a flow is active and flow->qentry is already set, smc_llc_flow_qentry_set() overwrites the pointer without freeing the previous allocation, leaking one kmalloc-96 object per spurious message. The sibling SMC_LLC_DELETE_LINK branch already has the correct !flow->qentry guard. Apply the same guard to the CONFIRM_LINK/ADD_LINK_CONT branch so that a duplicate message when qentry is already occupied falls through to break and is freed by the kfree(qentry) at the out: label, rather than silently leaking the existing allocation. The response direction (smc_llc_rx_response()) is unaffected: it already guards with flow->qentry at the equivalent site and drops duplicate responses correctly.

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

    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
    • 6.13 – < 6.18.45
    • 5.8 – < 5.10.265
    • 5.11 – < 5.15.216
    • 5.16 – < 6.1.183
    • 6.19 – < 7.1.9
    • 6.7 – < 6.12.104
    • 6.2 – < 6.6.152
    • —
    • 6.18.45
    • 5.10.265
    • 5.15.216
    • 6.1.183
    • 7.1.9
    • 6.12.104
    • 6.6.152
    • 7.2

    Vendors and products

    Affected operating systems

    Affected operating systems
    Linuxdebianlinuxbookworm
    Linuxdebianlinuxtrixie
    Linuxubuntulinuxresolute
    Linuxdebianlinux-6.12bookworm
    Linuxubuntulinux-awsresolute
    Linuxubuntulinux-gcpresolute
    Linuxubuntulinux-hwe-7.0noble
    Linuxubuntulinux-ibmresolute
    Linuxubuntulinux-nvidiajammy
    Linuxubuntulinux-nvidia-tegrajammy
    Linuxubuntulinux-nvidia-tegra-5.15focal
    Linuxubuntulinux-nvidia-tegra-igxjammy
    Linuxubuntulinux-oem-7.0resolute
    Linuxubuntulinux-oracleresolute

    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. ReceivedLinux

      Description added or changed

      Show 10 original changes
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Affected versions (publisher)added
      —
      Linux, Linux
      Descriptionadded
      —
      In the Linux kernel, the following vulnerability has been resolved: net/smc: fix qentry overwrite for CONFIRM_LINK and ADD_LINK_CONT in smc_llc_event_handler() The SMC_LLC_CONFIRM_LINK / SMC_LLC_ADD_LINK_CONT branch in smc_llc_event_handler() stores an incoming qentry into the local LLC flow without first checking whether a qentry is already pending. If a malicious or buggy peer sends a second CONFIRM_LINK or ADD_LINK_CONT request while a flow is active and flow->qentry is already set, smc_llc_flow_qentry_set() overwrites the pointer without freeing the previous allocation, leaking one kmalloc-96 object per spurious message. The sibling SMC_LLC_DELETE_LINK branch already has the correct !flow->qentry guard. Apply the same guard to the CONFIRM_LINK/ADD_LINK_CONT branch so that a duplicate message when qentry is already occupied falls through to break and is freed by the kfree(qentry) at the out: label, rather than silently leaking the existing allocation. The response direction (smc_llc_rx_response()) is unaffected: it already guards with flow->qentry at the equivalent site and drops duplicate responses correctly.
      Referenceadded
      —
      https://git.kernel.org/stable/c/06734dfeaeba886aab1bf147249195b888ac3e4d
      Referenceadded
      —
      https://git.kernel.org/stable/c/10cb31b2b74cb664c6c95cf72364d7d5c483ab82
      Referenceadded
      —
      https://git.kernel.org/stable/c/976245094925bab9bc39366b2e9ab44ffcde61d0
      Referenceadded
      —
      https://git.kernel.org/stable/c/a1e980d7a9e7ee6faf4f5fd7b450413b969af26d
      Referenceadded
      —
      https://git.kernel.org/stable/c/bfc336a9fbbf09805f3dfe25c195a4db90af2846
      Referenceadded
      —
      https://git.kernel.org/stable/c/c23c409228629107203d3c3e95fff1473173f1a6
      Referenceadded
      —
      https://git.kernel.org/stable/c/e0eb87677c76b157cdf8eb7c1f19e56227165a33
      Referenceadded
      —
      https://git.kernel.org/stable/c/e384f3cba6ea709f5b2272b1770db4ce14047f78

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

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