HighCVE-2025-39902

    Linux Kernel: security vulnerability (CVE-2025-39902)

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

    What is affected, what to do

    In the Linux kernel, the following vulnerability has been resolved: mm/slub: avoid accessing metadata when pointer is invalid in object_err() object_err() reports details of an object for further debugging, such as the freelist pointer, redzone, etc. However, if the pointer is invalid, attempting to access object metadata can lead to a crash since it does not point to a valid object. One known path to the crash is when alloc_consistency_checks() determines the pointer to the allocated object is invalid because of a freelist corruption, and calls object_err() to report it.

    Update Linux Kernel to version 5.4.299, Linux Kernel to version 5.10.243, Linux Kernel to version 5.15.192.

    Affected
    • Linux Kernel lt 2.6.22..5.4.299
    • Linux Kernel lt 5.5..5.10.243
    • Linux Kernel lt 5.11..5.15.192
    • Linux Kernel lt 5.16..6.1.151
    • Linux Kernel lt 6.2..6.6.105
    • Linux Kernel lt 6.7..6.12.46
    • Linux Kernel lt 6.13..6.16.6
    Fixed in
    • Linux Kernel 5.4.299
    • Linux Kernel 5.10.243
    • Linux Kernel 5.15.192
    • Linux Kernel 6.1.151
    • Linux Kernel 6.6.105
    • Linux Kernel 6.12.46
    • Linux Kernel 6.16.6
    • Linux Kernel 6.17

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

    Metrics

    7.1

    Priority

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

    Source: Vendor (CNA), CVSS v3

    7.1

    CVSS v3

    Severity High on the scale from 0 to 10.

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

    0.2 %

    EPSS score

    Low — model estimates < 1% exploitation likelihood.

    Source: FIRST EPSS, percentile 6.0

    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
    46.93 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
    7.1 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
    7.1
    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
    6.0
    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
    CISA assessment (SSVC)
    Exploitation: none known · not automatable · Technical impact: partial
    Source: CISA Vulnrichment, as of 15 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: mm/slub: avoid accessing metadata when pointer is invalid in object_err() object_err() reports details of an object for further debugging, such as the freelist pointer, redzone, etc. However, if the pointer is invalid, attempting to access object metadata can lead to a crash since it does not point to a valid object. One known path to the crash is when alloc_consistency_checks() determines the pointer to the allocated object is invalid because of a freelist corruption, and calls object_err() to report it. The debug code should report and handle the corruption gracefully and not crash in the process. In case the pointer is NULL or check_valid_pointer() returns false for the pointer, only print the pointer value and skip accessing metadata.

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

    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
    • 6.2 – < 6.6.105
    • 5.11 – < 5.15.192
    • 2.6.22 – < 5.4.299
    • 5.16 – < 6.1.151
    • 5.5 – < 5.10.243
    • 6.13 – < 6.16.6
    • —
    • 6.7 – < 6.12.46
    • 6.6.105
    • 5.15.192
    • 5.4.299
    • 6.1.151
    • 5.10.243
    • 6.16.6
    • 6.17
    • 6.12.46
    IBMQRadar SIEM
    • < 7.6.0.3
    • <7.5.0 UP16 IF01
    • 7.6.0.3
    • —

    Vendors and products

    Affected operating systems

    Affected operating systems
    Linuxdebiandebian_linux11.0
    Linuxdebianlinuxbullseye
    Linuxdebianlinux-6.1bullseye
    Linuxlinuxlinux_kernel6.17
    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/0ef7058b4dc6fcef622ac23b45225db57f17b83f
      Referenceadded
      —
      https://git.kernel.org/stable/c/1f0797f17927b5cad0fb7eced422f9a7c30a3191
      Referenceadded
      —
      https://git.kernel.org/stable/c/3baa1da473e6e50281324ff1d332d1a07a3bb02e
      Referenceadded
      —
      https://git.kernel.org/stable/c/7e287256904ee796c9477e3ec92b07f236481ef3
      Referenceadded
      —
      https://git.kernel.org/stable/c/872f2c34ff232af1e65ad2df86d61163c8ffad42
      Referenceadded
      —
      https://git.kernel.org/stable/c/b4efccec8d06ceb10a7d34d7b1c449c569d53770
      Referenceadded
      —
      https://git.kernel.org/stable/c/dda6ec365ab04067adae40ef17015db447e90736
      Referenceadded
      —
      https://git.kernel.org/stable/c/f66012909e7bf383fcdc5850709ed5716073fdc4
      Referenceremoved
      https://git.kernel.org/stable/c/0ef7058b4dc6fcef622ac23b45225db57f17b83f
      —
      Referenceremoved
      https://git.kernel.org/stable/c/1f0797f17927b5cad0fb7eced422f9a7c30a3191
      —
      Referenceremoved
      https://git.kernel.org/stable/c/3baa1da473e6e50281324ff1d332d1a07a3bb02e
      —
      Referenceremoved
      https://git.kernel.org/stable/c/7e287256904ee796c9477e3ec92b07f236481ef3
      —
      Referenceremoved
      https://git.kernel.org/stable/c/872f2c34ff232af1e65ad2df86d61163c8ffad42
      —
      Referenceremoved
      https://git.kernel.org/stable/c/b4efccec8d06ceb10a7d34d7b1c449c569d53770
      —
      Referenceremoved
      https://git.kernel.org/stable/c/dda6ec365ab04067adae40ef17015db447e90736
      —
      Referenceremoved
      https://git.kernel.org/stable/c/f66012909e7bf383fcdc5850709ed5716073fdc4
      —
      Reference typeremoved
      https://git.kernel.org/stable/c/0ef7058b4dc6fcef622ac23b45225db57f17b83f Types: Patch
      —
      Reference typeremoved
      https://git.kernel.org/stable/c/1f0797f17927b5cad0fb7eced422f9a7c30a3191 Types: Patch
      —
      Reference typeremoved
      https://git.kernel.org/stable/c/3baa1da473e6e50281324ff1d332d1a07a3bb02e Types: Patch
      —
      Reference typeremoved
      https://git.kernel.org/stable/c/7e287256904ee796c9477e3ec92b07f236481ef3 Types: Patch
      —
      Reference typeremoved
      https://git.kernel.org/stable/c/872f2c34ff232af1e65ad2df86d61163c8ffad42 Types: Patch
      —
      Reference typeremoved
      https://git.kernel.org/stable/c/b4efccec8d06ceb10a7d34d7b1c449c569d53770 Types: Patch
      —
      Reference typeremoved
      https://git.kernel.org/stable/c/dda6ec365ab04067adae40ef17015db447e90736 Types: Patch
      —
      Reference typeremoved
      https://git.kernel.org/stable/c/f66012909e7bf383fcdc5850709ed5716073fdc4 Types: Patch
      —

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

    2. Record modifiedCISA ADP

      CISA assessment (SSVC): exploitation: none known, automatable: no

      Show the original change
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      SSVC assessmentadded
      —
      {"id":"CVE-2025-39902","role":"CISA Coordinator","options":[{"exploitation":"none"},{"automatable":"no"},{"technicalImpact":"partial"}],"version":"2.0.3","timestamp":"2026-10-15T21:54:38.930497Z"}

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

    3. Record modifiedCVE Program

      Show 6 original changes
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Referenceadded
      —
      https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html
      Referenceadded
      —
      https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html
      Referenceremoved
      https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html
      —
      Referenceremoved
      https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html
      —
      Reference typeremoved
      https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html Types: Third Party Advisory
      —
      Reference typeremoved
      https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html Types: Third Party Advisory
      —

      Source identifier: af854a3a-2127-422b-91ae-364da2661108

    4. Record modifiedLinux

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

      Show the original change
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      CVSSadded
      —
      AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

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

    One NVD translation into another language is hidden.

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