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Full vulnerability report · 2026
CVE-2026-23002High confidence

lib/buildid: use __kernel_read() for sleepable context

Linux · Linux

5.5MediumCVSS 3.1
Recommended action
Scheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Patch available
Distribution package intelligence

Ubuntu vendor package status

Canonical’s release and source-package findings are shown separately from local repository availability.

13 package states
Repository candidate not checked

A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.

Ubuntu releaseSource packageVendor stateFixed versionEvidence
Ubuntu 24.04 LTSnoble · standard archivelinux-aws-6.14Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 11 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-azure-6.11Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 11 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-azure-fde-6.14Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 11 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-azure-nvidia-6.14Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 11 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-gcp-6.11Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 11 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-hwe-6.11Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 11 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-lowlatency-hwe-6.11Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 11 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-nvidia-6.11Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 11 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-oem-6.11Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 11 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-oracle-6.14Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 11 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-raspi-realtimeAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 11 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-realtimeAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 11 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-riscvAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 11 Sept 2026
Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Select the national-authority views to include. The exact source language is shown on each matched advisory. Your choice is remembered on this device and encoded in the shareable URL.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2026-4620

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
Not supplied in the stored EUVD record
Advisory evidence
No linked advisory details stored yet
Recommended actionScheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Patch available
01

What, why and how

In the Linux kernel, the following vulnerability has been resolved: lib/buildid: use __kernel_read() for sleepable context Prevent a "BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio". For the sleepable context, convert freader to use __kernel_read() instead of direct page cache access via read_cache_folio(). This simplifies the faultable code path by using the standard kernel file reading interface which handles all the complexity of reading file data. At the moment we are not changing the code for non-sleepable context which uses filemap_get_folio() and only succeeds if the target folios are already in memory and up-to-date. The reason is to keep the patch simple and easier to backport to stable kernels. Syzbot repro does not crash the kernel anymore and the selftests run successfully. In the follow up we will make __kernel_read() with IOCB_NOWAIT work for non-sleepable contexts. In addition, I would like to replace the secretmem check with a more generic approach and will add fstest for the buildid code.

What

In the Linux kernel, the following vulnerability has been resolved: lib/buildid: use __kernel_read() for sleepable context Prevent a "BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio". For the sleepable context, convert freader to use __kernel_read() instead of direct page cache access via read_cache_folio(). This simplifies the faultable code path by using the standard kernel file reading interface which handles all the complexity of reading file data. At the moment we are not changing the code for non-sleepable context which uses filemap_get_folio() and only succeeds if the target folios are already in memory and up-to-date. The reason is to keep the patch simple and easier to backport to stable kernels. Syzbot repro does not crash the kernel anymore and the selftests run successfully. In the follow up we will make __kernel_read() with IOCB_NOWAIT work for non-sleepable contexts. In addition, I would like to replace the secretmem check with a more generic approach and will add fstest for the buildid code.

Why

The product dereferences a pointer that it expects to be valid but is NULL.

How

An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may disrupt the affected service.

What

In the Linux kernel, the following vulnerability has been resolved: lib/buildid: use __kernel_read() for sleepable context Prevent a "BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio". For the sleepable context, convert freader to use __kernel_read() instead of direct page cache access via read_cache_folio(). This simplifies the faultable code path by using the standard kernel file reading interface which handles all the complexity of reading file data. At the moment we are not changing the code for non-sleepable context which uses filemap_get_folio() and only succeeds if the target folios are already in memory and up-to-date. The reason is to keep the patch simple and easier to backport to stable kernels. Syzbot repro does not crash the kernel anymore and the selftests run successfully. In the follow up we will make __kernel_read() with IOCB_NOWAIT work for non-sleepable contexts. In addition, I would like to replace the secretmem check with a more generic approach and will add fstest for the buildid code.

Why

The product dereferences a pointer that it expects to be valid but is NULL.

How

An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may disrupt the affected service.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path
local access → NULL Pointer Dereference → disrupt the affected service
Attack surface
Local
Privileges required
Low: a basic authenticated account is required
User interaction
None
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-476

CWE-476: NULL Pointer Dereference. The product dereferences a pointer that it expects to be valid but is NULL.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVLocalAttack vector: The attacker needs local access to the vulnerable system.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRLowPrivileges required: The attacker needs basic user-level privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CNoneConfidentiality impact: No direct loss is represented by this metric.INoneIntegrity impact: No direct loss is represented by this metric.AHighAvailability impact: A successful attack can cause a major loss.
Post-exploitation / living off the land
The issue can support a local privilege or sandbox boundary transition; normal system utilities may then be available in the gained context.
Denial of serviceCWE-476
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

BSI · German · WID-SEC-2026-0215Linux Kernel: Mehrere Schwachstellen

Ein Angreifer kann mehrere Schwachstellen im Linux Kernel ausnutzen, um nicht näher spezifizierte Angriffe durchzuführen, die möglicherweise zu einer Denial-of-Service- Bedingung führen oder eine Speicherbeschädigung verursachen können.

Official advisory ↗
Cyber Security Agency of Singapore · English · CSA-SB-20260128Security Bulletin 28 Jan 2026

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 28 Jan 2026, published on 28 January 2026. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗
CERT-FR · French · CERTFR-2026-AVI-1093Multiples vulnérabilités dans le noyau Linux d'Ubuntu

d?id=CVE-2026-22992 Référence CVE CVE-2026-22993 https://www.cve.org/CVERecord?id=CVE-2026-22993 Référence CVE CVE-2026-22994 https://www.cve.org/CVERecord?id=CVE-2026-22994 Référence CVE CVE-2026-22996 https://www.cve.org/CVERecord?id=CVE-2026-22996 Référence CVE CVE-2026-22997 https://www.cve.org/CVERecord?id=CVE-2026-22997 Référence CVE CVE-2026-22998 https://www.cve.org/CVERecord?id=CVE-2026-22998 Référence CVE CVE-2026-22999 https://www.cve.org/CVERecord?id=CVE-2026-22999 Référence CVE CVE-2026-23000 https://www.cve.org/CVERecord?id=CVE-2026-23000 Référence CVE CVE-2026-23001 https://www.cve.org/CVERecord?id=CVE-2026-23001 Référence CVE CVE-2026-23002 https://www.cve.org/CVERecord?id=CVE-2026-23002 Référence CVE CVE-2026-23003 https://www.cve.org/CVERecord?id=CVE-2026-23003 Référence CVE CVE-2026-23004 https://www.cve.org/CVERecord?id=CVE-2026-23004 Référence CVE CVE-2026-23005 https://www.cve.org/CVERecord?id=CVE-2026-23005 Référence CVE CVE-2026-23006 https://www.cve.org/CVERecord?id=CVE-2026-23006 Référence CVE CVE-2026-23007 https://www.cve.org/CVERecord?id=CVE-2026-23007 Référence CVE CVE-2026-23008 https://www.cve.org/CVERecord?id=CVE-2026-23008 Référence CVE CVE-2026-23009 https://www.cve.org/CVERecord?id=CVE-2026-23009 Référence CVE CVE-2026-23010 https://www.cve.org/CVERecord?id=

Official advisory ↗
CERT-FR · French · CERTFR-2026-AVI-0954Multiples vulnérabilités dans le noyau Linux d'Ubuntu

d?id=CVE-2026-22992 Référence CVE CVE-2026-22993 https://www.cve.org/CVERecord?id=CVE-2026-22993 Référence CVE CVE-2026-22994 https://www.cve.org/CVERecord?id=CVE-2026-22994 Référence CVE CVE-2026-22996 https://www.cve.org/CVERecord?id=CVE-2026-22996 Référence CVE CVE-2026-22997 https://www.cve.org/CVERecord?id=CVE-2026-22997 Référence CVE CVE-2026-22998 https://www.cve.org/CVERecord?id=CVE-2026-22998 Référence CVE CVE-2026-22999 https://www.cve.org/CVERecord?id=CVE-2026-22999 Référence CVE CVE-2026-23000 https://www.cve.org/CVERecord?id=CVE-2026-23000 Référence CVE CVE-2026-23001 https://www.cve.org/CVERecord?id=CVE-2026-23001 Référence CVE CVE-2026-23002 https://www.cve.org/CVERecord?id=CVE-2026-23002 Référence CVE CVE-2026-23003 https://www.cve.org/CVERecord?id=CVE-2026-23003 Référence CVE CVE-2026-23004 https://www.cve.org/CVERecord?id=CVE-2026-23004 Référence CVE CVE-2026-23005 https://www.cve.org/CVERecord?id=CVE-2026-23005 Référence CVE CVE-2026-23006 https://www.cve.org/CVERecord?id=CVE-2026-23006 Référence CVE CVE-2026-23007 https://www.cve.org/CVERecord?id=CVE-2026-23007 Référence CVE CVE-2026-23008 https://www.cve.org/CVERecord?id=CVE-2026-23008 Référence CVE CVE-2026-23009 https://www.cve.org/CVERecord?id=CVE-2026-23009 Référence CVE CVE-2026-23010 https://www.cve.org/CVERecord?id=

Official advisory ↗
CERT-FR · French · CERTFR-2026-AVI-0926Multiples vulnérabilités dans le noyau Linux d'Ubuntu

d?id=CVE-2026-22992 Référence CVE CVE-2026-22993 https://www.cve.org/CVERecord?id=CVE-2026-22993 Référence CVE CVE-2026-22994 https://www.cve.org/CVERecord?id=CVE-2026-22994 Référence CVE CVE-2026-22996 https://www.cve.org/CVERecord?id=CVE-2026-22996 Référence CVE CVE-2026-22997 https://www.cve.org/CVERecord?id=CVE-2026-22997 Référence CVE CVE-2026-22998 https://www.cve.org/CVERecord?id=CVE-2026-22998 Référence CVE CVE-2026-22999 https://www.cve.org/CVERecord?id=CVE-2026-22999 Référence CVE CVE-2026-23000 https://www.cve.org/CVERecord?id=CVE-2026-23000 Référence CVE CVE-2026-23001 https://www.cve.org/CVERecord?id=CVE-2026-23001 Référence CVE CVE-2026-23002 https://www.cve.org/CVERecord?id=CVE-2026-23002 Référence CVE CVE-2026-23003 https://www.cve.org/CVERecord?id=CVE-2026-23003 Référence CVE CVE-2026-23004 https://www.cve.org/CVERecord?id=CVE-2026-23004 Référence CVE CVE-2026-23005 https://www.cve.org/CVERecord?id=CVE-2026-23005 Référence CVE CVE-2026-23006 https://www.cve.org/CVERecord?id=CVE-2026-23006 Référence CVE CVE-2026-23007 https://www.cve.org/CVERecord?id=CVE-2026-23007 Référence CVE CVE-2026-23008 https://www.cve.org/CVERecord?id=CVE-2026-23008 Référence CVE CVE-2026-23009 https://www.cve.org/CVERecord?id=CVE-2026-23009 Référence CVE CVE-2026-23010 https://www.cve.org/CVERecord?id=

Official advisory ↗
CERT-FR · French · CERTFR-2026-AVI-0247Multiples vulnérabilités dans le noyau Linux de SUSE

d?id=CVE-2026-22990 Référence CVE CVE-2026-22991 https://www.cve.org/CVERecord?id=CVE-2026-22991 Référence CVE CVE-2026-22992 https://www.cve.org/CVERecord?id=CVE-2026-22992 Référence CVE CVE-2026-22993 https://www.cve.org/CVERecord?id=CVE-2026-22993 Référence CVE CVE-2026-22996 https://www.cve.org/CVERecord?id=CVE-2026-22996 Référence CVE CVE-2026-22997 https://www.cve.org/CVERecord?id=CVE-2026-22997 Référence CVE CVE-2026-22999 https://www.cve.org/CVERecord?id=CVE-2026-22999 Référence CVE CVE-2026-23000 https://www.cve.org/CVERecord?id=CVE-2026-23000 Référence CVE CVE-2026-23001 https://www.cve.org/CVERecord?id=CVE-2026-23001 Référence CVE CVE-2026-23002 https://www.cve.org/CVERecord?id=CVE-2026-23002 Référence CVE CVE-2026-23005 https://www.cve.org/CVERecord?id=CVE-2026-23005 Référence CVE CVE-2026-23006 https://www.cve.org/CVERecord?id=CVE-2026-23006 Référence CVE CVE-2026-23010 https://www.cve.org/CVERecord?id=CVE-2026-23010 Référence CVE CVE-2026-23011 https://www.cve.org/CVERecord?id=CVE-2026-23011 Gestion détaillée du document le 06 mars 2026 Version initiale Alertes Avis Bulletins d’actualités Mentions légales Conditions générales À propos Contact cyber.gouv.fr service-public.fr legifrance.gouv.fr info.gouv.fr france.fr info.gouv.fr/risques Premier Ministre / Secrétariat Général de la

Official advisory ↗
CERT-FR · French · CERTFR-2026-AVI-0166Multiples vulnérabilités dans le noyau Linux de Debian

d?id=CVE-2026-22991 Référence CVE CVE-2026-22992 https://www.cve.org/CVERecord?id=CVE-2026-22992 Référence CVE CVE-2026-22994 https://www.cve.org/CVERecord?id=CVE-2026-22994 Référence CVE CVE-2026-22996 https://www.cve.org/CVERecord?id=CVE-2026-22996 Référence CVE CVE-2026-22997 https://www.cve.org/CVERecord?id=CVE-2026-22997 Référence CVE CVE-2026-22998 https://www.cve.org/CVERecord?id=CVE-2026-22998 Référence CVE CVE-2026-22999 https://www.cve.org/CVERecord?id=CVE-2026-22999 Référence CVE CVE-2026-23000 https://www.cve.org/CVERecord?id=CVE-2026-23000 Référence CVE CVE-2026-23001 https://www.cve.org/CVERecord?id=CVE-2026-23001 Référence CVE CVE-2026-23002 https://www.cve.org/CVERecord?id=CVE-2026-23002 Référence CVE CVE-2026-23003 https://www.cve.org/CVERecord?id=CVE-2026-23003 Référence CVE CVE-2026-23005 https://www.cve.org/CVERecord?id=CVE-2026-23005 Référence CVE CVE-2026-23006 https://www.cve.org/CVERecord?id=CVE-2026-23006 Référence CVE CVE-2026-23010 https://www.cve.org/CVERecord?id=CVE-2026-23010 Référence CVE CVE-2026-23011 https://www.cve.org/CVERecord?id=CVE-2026-23011 Référence CVE CVE-2026-23013 https://www.cve.org/CVERecord?id=CVE-2026-23013 Référence CVE CVE-2026-23019 https://www.cve.org/CVERecord?id=CVE-2026-23019 Référence CVE CVE-2026-23020 https://www.cve.org/CVERecord?id=

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2026-008924LinuxのLinux KernelにおけるNULL ポインタデリファレンスに関する脆弱性

Linuxカーネルにおいて以下の脆弱性が修正されました。lib/buildidではスリープ可能なコンテキストで__kernel_read()を使用するように変更し、「BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio」を防止しました。スリープ可能なコンテキストでは、freaderをread_cache_folio()を介した直接のページキャッシュアクセスの代わりに__kernel_read()を用いるように変換しました。これにより、ファイルデータの読み取りの複雑さをすべて処理する標準的なカーネルファイル読み取りインターフェースを使用するため、障害が発生しやすいコードパスが簡素化されます。現時点ではfilemap_get_folio()を使用し、対象のフォリオがすでにメモリ内で最新である場合にのみ成功するスリープ不可能なコンテキストのコードは変更していません。これはパッチをシンプルに保ち、安定カーネルへのバックポートを容易にするためです。Syzbotによる再現はもはやカーネルをクラッシュさせず、セルフテストも正常に実行されています。今後の対応としてスリープ不可能なコンテキスト用にIOCB_NOWAIT付きの__kernel_read()を機能させる予定です。加えて、secretmemチェックをより汎用的なアプローチに置き換え、buildidコード用のfstestも追加します。

Official advisory ↗
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Patch available
Affected
Linux: ad41251c290dfe3c01472c94d2439a59de23fe97 < b11dfb7708f212b96c7973a474014c071aa02e05, ad41251c290dfe3c01472c94d2439a59de23fe97 < 568aeb3476c770a3863c755dd2a199c212434286, ad41251c290dfe3c01472c94d2439a59de23fe97 < 777a8560fd29738350c5094d4166fe5499452409, 6.12
Fixed
Linux: < 6.12, 6.12.67 ≤ 6.12.*, 6.18.7 ≤ 6.18.*, 6.19 ≤ *
Action
Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
Workaround
No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.
04

Evidence and provenance

Published 25 Jan 2026 · Last source change 11 May 2026, 21:58 UTC · CWE-476 · NULL Pointer Dereference

CVE recordCVE.org · 5.2
CVSS sourceNIST NVD
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-14
European sourceENISA EUVD · EUVD-2026-4620
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceNIST NVD
NVD statusNVD enriched

Core structured fields are present and their contributing authorities are shown above.

Material change intelligence

What changed after publication

View recent updates ↗

No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.

Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2026-23002 · cve.blacktree.nl