CriticalCVE-2026-74427

    Linux Kernel: security vulnerability (CVE-2026-74427)

    Published Last modified Sources: Ubuntu, CVE.org, BSI

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    What is affected, what to do

    In the Linux kernel, the following vulnerability has been resolved: afs: Fix netns teardown to cancel the preallocation charger Fix the teardown of an afs network namespace to make sure it cancels the work item that keeps the preallocated rxrpc call/conn/peer queue charged before incoming calls are disabled (i.e. listen 0). Also, if net->live is false because the afs netns is being deleted, make afs_charge_preallocation() skip charging and make afs_rx_new_call() avoid requeuing the charger.

    Update Linux Kernel to version 5.10.261, Linux Kernel to version 5.15.212, Linux Kernel to version 6.1.178.

    Affected
    • Linux Kernel lt 4.9..5.10.261
    • Linux Kernel lt 5.11..5.15.212
    • Linux Kernel lt 5.16..6.1.178
    • Linux Kernel lt 6.2..6.6.145
    • Linux Kernel lt 6.7..6.12.97
    • Linux Kernel lt 6.13..6.18.40
    • Linux Kernel lt 6.19..7.1.5
    Fixed in
    • Linux Kernel 5.10.261
    • Linux Kernel 5.15.212
    • Linux Kernel 6.1.178
    • Linux Kernel 6.6.145
    • Linux Kernel 6.12.97
    • Linux Kernel 6.18.40
    • Linux Kernel 7.1.5
    • Linux Kernel 7.2

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

    Metrics

    9.8

    Priority

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

    Source: Vendor (CNA), CVSS v3

    9.8

    CVSS v3

    Severity Critical on the scale from 0 to 10.

    Source: Ubuntu, CVE.org, BSI

    0.8 %

    EPSS score

    Low — model estimates < 1% exploitation likelihood.

    Source: FIRST EPSS, percentile 55.2

    Show all metrics
    Severity
    Critical
    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
    96.10 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
    9.8 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
    9.8
    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
    0.8 %
    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
    55.2
    High — this CVE ranks above the median of all CVEs scored today (rank ≥ 36%).
    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
    CISA assessment (SSVC)
    Exploitation: none known · automatable · Technical impact: total
    Source: CISA Vulnrichment, as of 16 October 2026

    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: afs: Fix netns teardown to cancel the preallocation charger Fix the teardown of an afs network namespace to make sure it cancels the work item that keeps the preallocated rxrpc call/conn/peer queue charged before incoming calls are disabled (i.e. listen 0). Also, if net->live is false because the afs netns is being deleted, make afs_charge_preallocation() skip charging and make afs_rx_new_call() avoid requeuing the charger. (This was found by AI review).

    Source: Ubuntu Security Notices, NVD (NIST), cvelistv5, BSI WID Portal, BSI CSAF

    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
    • 6.7 – < 6.12.97
    • 6.19 – < 7.1.5
    • 5.11 – < 5.15.212
    • 6.2 – < 6.6.145
    • 4.9 – < 5.10.261
    • —
    • 6.13 – < 6.18.40
    • 5.16 – < 6.1.178
    • 6.12.97
    • 7.1.5
    • 5.15.212
    • 6.6.145
    • 5.10.261
    • 7.2
    • 6.18.40
    • 6.1.178

    Vendors and products

    Affected operating systems

    Affected operating systems
    Linuxubuntulinuxnoble
    Linuxubuntulinuxresolute
    Linuxubuntulinux-awsnoble
    Linuxubuntulinux-awsresolute
    Linuxubuntulinux-aws-7.0noble
    Linuxubuntulinux-aws-fipsnoble
    Linuxubuntulinux-azurenoble
    Linuxubuntulinux-azureresolute
    Linuxubuntulinux-azure-7.0noble
    Linuxubuntulinux-azure-fdenoble
    Linuxubuntulinux-azure-fderesolute
    Linuxubuntulinux-azure-fde-7.0noble
    Linuxubuntulinux-azure-fipsnoble
    Linuxubuntulinux-fipsnoble
    Linuxubuntulinux-gcpnoble
    Linuxubuntulinux-gcp-fipsnoble
    Linuxubuntulinux-gkenoble
    Linuxubuntulinux-gkeopnoble
    Linuxubuntulinux-hwe-7.0noble
    Linuxubuntulinux-ibmnoble
    Linuxubuntulinux-ibmresolute
    Linuxubuntulinux-lowlatencynoble
    Linuxubuntulinux-nvidiajammy
    Linuxubuntulinux-nvidia-tegrajammy

    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 modifiedCISA ADP

      CISA assessment (SSVC): exploitation: none known, automatable: yes

      Show the original change
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      SSVC assessmentadded
      —
      {"id":"CVE-2026-74427","role":"CISA Coordinator","options":[{"exploitation":"none"},{"automatable":"yes"},{"technicalImpact":"total"}],"version":"2.0.3","timestamp":"2026-10-16T18:56:19.118841Z"}

      Source identifier: 134c704f-9b21-4f2e-91b3-4a467353bcc0

    2. Record modifiedLinux

      Show 16 original changes
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Referenceadded
      —
      https://git.kernel.org/stable/c/47694fbc9d24ab6bf210f91e8efe06a10a478064
      Referenceadded
      —
      https://git.kernel.org/stable/c/59e8b7652f6cbfb62d377ead0ad553c1b4e39a7a
      Referenceadded
      —
      https://git.kernel.org/stable/c/63ccaf1bdf8be2330f47f9b5b233dd3fd04acbd9
      Referenceadded
      —
      https://git.kernel.org/stable/c/85d5fb80fe4f0cc836b6df83f26de204fe102ff7
      Referenceadded
      —
      https://git.kernel.org/stable/c/a33975ff2b6ea47b8f29956403374b1cdd057539
      Referenceadded
      —
      https://git.kernel.org/stable/c/b83ecf80e28afb7b6595ba79932e77ca68a5a83d
      Referenceadded
      —
      https://git.kernel.org/stable/c/eec89c5f8e1adc1de4824042ef75f62aed804153
      Referenceadded
      —
      https://git.kernel.org/stable/c/f5096e18b6b7fbd1c2a1942e275a51bcfdfb2ad1
      Referenceremoved
      https://git.kernel.org/stable/c/47694fbc9d24ab6bf210f91e8efe06a10a478064
      —
      Referenceremoved
      https://git.kernel.org/stable/c/59e8b7652f6cbfb62d377ead0ad553c1b4e39a7a
      —
      Referenceremoved
      https://git.kernel.org/stable/c/63ccaf1bdf8be2330f47f9b5b233dd3fd04acbd9
      —
      Referenceremoved
      https://git.kernel.org/stable/c/85d5fb80fe4f0cc836b6df83f26de204fe102ff7
      —
      Referenceremoved
      https://git.kernel.org/stable/c/a33975ff2b6ea47b8f29956403374b1cdd057539
      —
      Referenceremoved
      https://git.kernel.org/stable/c/b83ecf80e28afb7b6595ba79932e77ca68a5a83d
      —
      Referenceremoved
      https://git.kernel.org/stable/c/eec89c5f8e1adc1de4824042ef75f62aed804153
      —
      Referenceremoved
      https://git.kernel.org/stable/c/f5096e18b6b7fbd1c2a1942e275a51bcfdfb2ad1
      —

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

    3. Record modifiedLinux

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

      Show 2 original changes
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      CVSSadded
      —
      AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
      Affected versions (publisher)changed
      Linux, Linux
      Linux, Linux

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

    4. 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: afs: Fix netns teardown to cancel the preallocation charger Fix the teardown of an afs network namespace to make sure it cancels the work item that keeps the preallocated rxrpc call/conn/peer queue charged before incoming calls are disabled (i.e. listen 0). Also, if net->live is false because the afs netns is being deleted, make afs_charge_preallocation() skip charging and make afs_rx_new_call() avoid requeuing the charger. (This was found by AI review).
      Referenceadded
      —
      https://git.kernel.org/stable/c/47694fbc9d24ab6bf210f91e8efe06a10a478064
      Referenceadded
      —
      https://git.kernel.org/stable/c/59e8b7652f6cbfb62d377ead0ad553c1b4e39a7a
      Referenceadded
      —
      https://git.kernel.org/stable/c/63ccaf1bdf8be2330f47f9b5b233dd3fd04acbd9
      Referenceadded
      —
      https://git.kernel.org/stable/c/85d5fb80fe4f0cc836b6df83f26de204fe102ff7
      Referenceadded
      —
      https://git.kernel.org/stable/c/a33975ff2b6ea47b8f29956403374b1cdd057539
      Referenceadded
      —
      https://git.kernel.org/stable/c/b83ecf80e28afb7b6595ba79932e77ca68a5a83d
      Referenceadded
      —
      https://git.kernel.org/stable/c/eec89c5f8e1adc1de4824042ef75f62aed804153
      Referenceadded
      —
      https://git.kernel.org/stable/c/f5096e18b6b7fbd1c2a1942e275a51bcfdfb2ad1

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

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