CriticalCVE-2026-53355

    Linux Kernel: security vulnerability (CVE-2026-53355)

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

    What is affected, what to do

    In the Linux kernel, the following vulnerability has been resolved: net: rds: clear i_sends on setup unwind The RDS IB connection teardown path is written so it can run during partial startup and on repeated shutdown attempts. It uses NULL pointers to distinguish resources that are still owned from resources that have already been released.

    Update Linux Kernel to version 3.19, Linux Kernel to version 4.2, Linux Kernel to version 4.5.

    Affected
    • Linux Kernel lt 3.18.74..3.19
    • Linux Kernel lt 4.1.46..4.2
    • Linux Kernel lt 4.4.91..4.5
    • Linux Kernel lt 4.9.54..4.10
    • Linux Kernel lt 4.11..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 3.19
    • Linux Kernel 4.2
    • Linux Kernel 4.5
    • Linux Kernel 4.10
    • 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

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

    0.4 %

    EPSS score

    Low — model estimates < 1% exploitation likelihood.

    Source: FIRST EPSS, percentile 36.3

    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
    79.44 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
    0.4 %
    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
    36.3
    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

    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: net: rds: clear i_sends on setup unwind The RDS IB connection teardown path is written so it can run during partial startup and on repeated shutdown attempts. It uses NULL pointers to distinguish resources that are still owned from resources that have already been released. When rds_ib_setup_qp() fails after allocating i_sends but before allocating i_recvs, the sends_out path frees i_sends without clearing the pointer. A later shutdown pass can still treat that stale pointer as a live send ring allocation. Clear i_sends after vfree() in the error unwind path so the existing shutdown logic continues to use the correct ownership state.

    Source: suse_csaf, Debian LTS Advisories, Ubuntu Security Notices, Microsoft Security Update Guide, cvelistv5, NVD (NIST), 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 – < 6.12.94
    • 6.13 – < 6.18.36
    • 5.11 – < 5.15.210
    • —
    • 4.1.46 – < 4.2
    • 3.18.74 – < 3.19
    • 4.9.54 – < 4.10
    • 5.16 – < 6.1.176
    • 4.4.91 – < 4.5
    • 6.19 – < 7.0.13
    • 4.11 – < 5.10.259
    • 6.2 – < 6.6.143
    • 6.12.94
    • 6.18.36
    • 5.15.210
    • 7.1
    • 4.2
    • 3.19
    • 4.10
    • 6.1.176
    • 4.5
    • 7.0.13
    • 5.10.259
    • 6.6.143

    Vendors and products

    Affected operating systems

    Affected operating systems
    Linuxdebianlinuxbookworm
    Linuxdebianlinuxbullseye
    Linuxubuntulinuxnoble
    Linuxdebianlinux-6.1bullseye
    Linuxubuntulinux-azurenoble
    Linuxubuntulinux-azure-6.8jammy
    Linuxubuntulinux-azure-fdenoble
    Linuxubuntulinux-azure-fde-6.8jammy
    Linuxubuntulinux-azure-fipsnoble
    Linuxubuntulinux-fipsnoble
    Linuxubuntulinux-gcpnoble
    Linuxubuntulinux-gcp-6.8jammy
    Linuxubuntulinux-gcp-fipsnoble
    Linuxubuntulinux-gkenoble
    Linuxubuntulinux-gkeopnoble
    Linuxubuntulinux-ibmnoble
    Linuxubuntulinux-lowlatencynoble
    Linuxubuntulinux-lowlatency-hwe-6.8jammy
    Linuxubuntulinux-oraclenoble
    Linuxubuntulinux-oracle-6.8jammy
    Linuxubuntulinux-raspinoble
    Linuxubuntulinux-raspi-realtimenoble
    Linuxubuntulinux-realtimenoble
    Linuxubuntulinux-realtime-6.8jammy

    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. Initial analysis by NVDNVD

      Newly listed as affected:
      • Linux Kernel (4.1.46 – before 4.2; 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; 4.11.1 – before 5.10.259; 3.18.74 – before 3.19; 4.4.91 – before 4.5; 4.9.54 – before 4.10; 13 individual versions)

      Weakness type: CWE-476

      Show 10 original changes
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Weakness type (CWE)added
      —
      CWE-476
      Product configurationadded
      —
      OR *cpe:2.3:o:linux:linux_kernel:4.11:rc5:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:4.11:rc3:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:4.11:rc4:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:4.11:rc6:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:4.11:rc7:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:4.11:rc8:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:4.11:-:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 4.1.46 up to (excluding) 4.2 *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:*:*:*:*:*:*:*:* versions from (including) 4.11.1 up to (excluding) 5.10.259 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 3.18.74 up to (excluding) 3.19 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 4.4.91 up to (excluding) 4.5 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 4.9.54 up to (excluding) 4.10
      Reference typeadded
      —
      kernel.org: https://git.kernel.org/stable/c/1d4ec754ee3871f7e3670c67bb0298c9c5760926 Types: Patch
      Reference typeadded
      —
      kernel.org: https://git.kernel.org/stable/c/20cf0fb715c41111469577e85e35d15f099473e0 Types: Patch
      Reference typeadded
      —
      kernel.org: https://git.kernel.org/stable/c/27040bbca289a704eafcacca167d310c6ce2b1bc Types: Patch
      Reference typeadded
      —
      kernel.org: https://git.kernel.org/stable/c/29d940026dce39e3018dab6f67c9427249321270 Types: Patch
      Reference typeadded
      —
      kernel.org: https://git.kernel.org/stable/c/2c5e5e4a5970c41f16e3ad801a78719ed5d5c71b Types: Patch
      Reference typeadded
      —
      kernel.org: https://git.kernel.org/stable/c/66cccec111421a10efdc2c74499d15b93e7acae5 Types: Patch
      Reference typeadded
      —
      kernel.org: https://git.kernel.org/stable/c/e7cf30aa5f1fc6c2a86df65df8b731df20e44d79 Types: Patch
      Reference typeadded
      —
      kernel.org: https://git.kernel.org/stable/c/f16ad421a4e3e7db2d14bdf3b16f583bc4f3b30a Types: Patch

      Source identifier: nvd@nist.gov

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