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Full vulnerability report · 2026
CVE-2026-43288High confidence

ext4: move ext4_percpu_param_init() before ext4_mb_init()

Linux · Linux

5.5MediumCVSS 3.1
Recommended action
Patch only the product branches with a verified fix

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority. Verified remediation exists for at least one product or source, but 21 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Fix availability varies by product
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityMediumOperational priority:Low, lowered one band.downgradedsince 14 Sep 2026

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • Exploitation requires an existing local or physical foothold with privileges.
  • EPSS is 0.17% for the current model date.

Compensating controls

  • Validate the affected product branch and deploy the verified fixed release.
  • Restrict local access and enforce least privilege on affected hosts.
  • Monitor vendor guidance and exploitation sources for a material change.

Verification

  1. Confirm that the asset runs Linux Linux and falls inside the recorded affected range.
  2. Verify the installed build against the product-specific fixed version after deployment.
  3. Validate exposure, authentication requirements and compensating controls in the actual environment.
  4. Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Mitigation target: No default targetRemediation target: Normal maintenance

This automated reassessment organises public evidence. It does not know asset exposure, business impact or control effectiveness and does not replace CVSS or a human risk decision.

Cross-source reconciliation

Remediation availability differs by product scope

Verified remediation exists for at least one product or source, but 21 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Distribution package intelligence

Release-specific package status

Debian, ubuntu findings are scoped to the named distribution, release and source package. An absent finding does not mean a package is unaffected.

24 package states
Package result overrides the generic status

BlackTree has verified remediation for at least one product or source, but the relevant distribution still reports no fixed package for 21 affected package states shown here. Treat those rows as affected with no fix until that distribution publishes a fixed version.

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.

Distribution releaseSource packageVendor stateFixed versionEvidence
Debian trixietrixie · sourcelinuxVendor fix publishedDebian records a fixed source-package version for this release.6.12.85-1Debian Security Tracker ↗Source updated 5 Oct 2026
Debian bookwormbookworm · sourcelinuxAffected, no fix publishedDebian currently tracks this release as open.Not published in this feedDebian Security Tracker ↗Source updated 5 Oct 2026
Debian forkyforky · sourcelinuxVendor fix publishedDebian records a fixed source-package version for this release.6.19.6-1Debian Security Tracker ↗Source updated 5 Oct 2026
Debian sidsid · sourcelinuxVendor fix publishedDebian records a fixed source-package version for this release.6.19.6-1Debian Security Tracker ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archivelinuxAffected, 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 Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-awsAffected, 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 Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-azureAffected, 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 Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-azure-fdeAffected, 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 Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-azure-nvidiaAffected, 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 Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-gcpAffected, 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 Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-gkeAffected, 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 Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-gkeopAffected, 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 Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-ibmAffected, 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 Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-lowlatencyAffected, 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 Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-nvidiaAffected, 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 Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-nvidia-lowlatencyAffected, 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 Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-nvidia-tegraAffected, 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 Ubuntu Security ↗Source updated 5 Oct 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 Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-oracleAffected, 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 Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-raspiAffected, 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 Ubuntu Security ↗Source updated 5 Oct 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 Ubuntu Security ↗Source updated 5 Oct 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 Ubuntu Security ↗Source updated 5 Oct 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 Ubuntu Security ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-xilinxAffected, 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 Ubuntu Security ↗Source updated 5 Oct 2026
Optional official sources

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

Choose official national sources for this report. Each advisory shows its original language. Your selection is remembered on this device and included in shared links.

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-2026-28558

No EUVD known-exploited evidence

In the Linux kernel, the following vulnerability has been resolved: ext4: move ext4_percpu_param_init() before ext4_mb_init() When running `kvm-xfstests -c ext4/1k -C 1 generic/383` with the `DOUBLE_CHECK` macro defined, the following panic is triggered: ================================================================== EXT4-fs error (device vdc): ext4_validate_block_bitmap:423: comm mount: bg 0: bad block bitmap checksum BUG: unable to handle page fault for address: ff110000fa2cc000 PGD 3e01067 P4D 3e02067 PUD 0 Oops: Oops: 0000 [#1] SMP NOPTI CPU: 0 UID: 0 PID: 2386 Comm: mount Tainted: G W 6.18.0-gba65a4e7120a-dirty #1152 PREEMPT(none) RIP: 0010:percpu_counter_add_batch+0x13/0xa0 Call Trace: <TASK> ext4_mark_group_bitmap_corrupted+0xcb/0xe0 ext4_validate_block_bitmap+0x2a1/0x2f0 ext4_read_block_bitmap+0x33/0x50 mb_group_bb_bitmap_alloc+0x33/0x80 ext4_mb_add_groupinfo+0x190/0x250 ext4_mb_init_backend+0x87/0x290 ext4_mb_init+0x456/0x640 __ext4_fill_super+0x1072/0x1680 ext4_fill_super+0xd3/0x280 get_tree_bdev_flags+0x132/0x1d0 vfs_get_tree+0x29/0xd0 vfs_cmd_create+0x59/0xe0 __do_sys_fsconfig+0x4f6/0x6b0 do_syscall_64+0x50/0x1f0 entry_SYSCALL_64_after_hwframe+0x76/0x7e ================================================================== This issue can be reproduced using the following commands: mkfs.ext4 -F -q -b 1024 /dev/sda 5G tune2fs -O quota,project /dev/sda mount /dev/sda /tmp/test With DOUBLE_CHECK defined, mb_group_bb_bitmap_alloc() reads and validates the block bitmap. When the validation fails, ext4_mark_group_bitmap_corrupted() attempts to update sbi->s_freeclusters_counter. However, this percpu_counter has not been initialized yet at this point, which leads to the panic described above. Fix this by moving the execution of ext4_percpu_param_init() to occur before ext4_mb_init(), ensuring the per-CPU counters are initialized before they are used.

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
0.0
Advisory evidence
No linked advisory details stored yet
Recommended actionPatch only the product branches with a verified fix

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority. Verified remediation exists for at least one product or source, but 21 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Fix availability varies by product
01

What, why and how

In the Linux kernel, the following vulnerability has been resolved: ext4: move ext4_percpu_param_init() before ext4_mb_init() When running `kvm-xfstests -c ext4/1k -C 1 generic/383` with the `DOUBLE_CHECK` macro defined, the following panic is triggered: ================================================================== EXT4-fs error (device vdc): ext4_validate_block_bitmap:423: comm mount: bg 0: bad block bitmap checksum BUG: unable to handle page fault for address: ff110000fa2cc000 PGD 3e01067 P4D 3e02067 PUD 0 Oops: Oops: 0000 [#1] SMP NOPTI CPU: 0 UID: 0 PID: 2386 Comm: mount Tainted: G W 6.18.0-gba65a4e7120a-dirty #1152 PREEMPT(none) RIP: 0010:percpu_counter_add_batch+0x13/0xa0 Call Trace: <TASK> ext4_mark_group_bitmap_corrupted+0xcb/0xe0 ext4_validate_block_bitmap+0x2a1/0x2f0 ext4_read_block_bitmap+0x33/0x50 mb_group_bb_bitmap_alloc+0x33/0x80 ext4_mb_add_groupinfo+0x190/0x250 ext4_mb_init_backend+0x87/0x290 ext4_mb_init+0x456/0x640 __ext4_fill_super+0x1072/0x1680 ext4_fill_super+0xd3/0x280 get_tree_bdev_flags+0x132/0x1d0 vfs_get_tree+0x29/0xd0 vfs_cmd_create+0x59/0xe0 __do_sys_fsconfig+0x4f6/0x6b0 do_syscall_64+0x50/0x1f0 entry_SYSCALL_64_after_hwframe+0x76/0x7e ================================================================== This issue can be reproduced using the following commands: mkfs.ext4 -F -q -b 1024 /dev/sda 5G tune2fs -O quota,project /dev/sda mount /dev/sda /tmp/test With DOUBLE_CHECK defined, mb_group_bb_bitmap_alloc() reads and validates the block bitmap. When the validation fails, ext4_mark_group_bitmap_corrupted() attempts to update sbi->s_freeclusters_counter. However, this percpu_counter has not been initialized yet at this point, which leads to the panic described above. Fix this by moving the execution of ext4_percpu_param_init() to occur before ext4_mb_init(), ensuring the per-CPU counters are initialized before they are used.

What

In the Linux kernel, the following vulnerability has been resolved: ext4: move ext4_percpu_param_init() before ext4_mb_init() When running `kvm-xfstests -c ext4/1k -C 1 generic/383` with the `DOUBLE_CHECK` macro defined, the following panic is triggered: ================================================================== EXT4-fs error (device vdc): ext4_validate_block_bitmap:423: comm mount: bg 0: bad block bitmap checksum BUG: unable to handle page fault for address: ff110000fa2cc000 PGD 3e01067 P4D 3e02067 PUD 0 Oops: Oops: 0000 [#1] SMP NOPTI CPU: 0 UID: 0 PID: 2386 Comm: mount Tainted: G W 6.18.0-gba65a4e7120a-dirty #1152 PREEMPT(none) RIP: 0010:percpu_counter_add_batch+0x13/0xa0 Call Trace: <TASK> ext4_mark_group_bitmap_corrupted+0xcb/0xe0 ext4_validate_block_bitmap+0x2a1/0x2f0 ext4_read_block_bitmap+0x33/0x50 mb_group_bb_bitmap_alloc+0x33/0x80 ext4_mb_add_groupinfo+0x190/0x250 ext4_mb_init_backend+0x87/0x290 ext4_mb_init+0x456/0x640 __ext4_fill_super+0x1072/0x1680 ext4_fill_super+0xd3/0x280 get_tree_bdev_flags+0x132/0x1d0 vfs_get_tree+0x29/0xd0 vfs_cmd_create+0x59/0xe0 __do_sys_fsconfig+0x4f6/0x6b0 do_syscall_64+0x50/0x1f0 entry_SYSCALL_64_after_hwframe+0x76/0x7e ================================================================== This issue can be reproduced using the following commands: mkfs.ext4 -F -q -b 1024 /dev/sda 5G tune2fs -O quota,project /dev/sda mount /dev/sda /tmp/test With DOUBLE_CHECK defined, mb_group_bb_bitmap_alloc() reads and validates the block bitmap. When the validation fails, ext4_mark_group_bitmap_corrupted() attempts to update sbi->s_freeclusters_counter. However, this percpu_counter has not been initialized yet at this point, which leads to the panic described above. Fix this by moving the execution of ext4_percpu_param_init() to occur before ext4_mb_init(), ensuring the per-CPU counters are initialized before they are used.

Why

The product uses or accesses a resource that has not been initialized.

How

An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

In the Linux kernel, the following vulnerability has been resolved: ext4: move ext4_percpu_param_init() before ext4_mb_init() When running `kvm-xfstests -c ext4/1k -C 1 generic/383` with the `DOUBLE_CHECK` macro defined, the following panic is triggered: ================================================================== EXT4-fs error (device vdc): ext4_validate_block_bitmap:423: comm mount: bg 0: bad block bitmap checksum BUG: unable to handle page fault for address: ff110000fa2cc000 PGD 3e01067 P4D 3e02067 PUD 0 Oops: Oops: 0000 [#1] SMP NOPTI CPU: 0 UID: 0 PID: 2386 Comm: mount Tainted: G W 6.18.0-gba65a4e7120a-dirty #1152 PREEMPT(none) RIP: 0010:percpu_counter_add_batch+0x13/0xa0 Call Trace: <TASK> ext4_mark_group_bitmap_corrupted+0xcb/0xe0 ext4_validate_block_bitmap+0x2a1/0x2f0 ext4_read_block_bitmap+0x33/0x50 mb_group_bb_bitmap_alloc+0x33/0x80 ext4_mb_add_groupinfo+0x190/0x250 ext4_mb_init_backend+0x87/0x290 ext4_mb_init+0x456/0x640 __ext4_fill_super+0x1072/0x1680 ext4_fill_super+0xd3/0x280 get_tree_bdev_flags+0x132/0x1d0 vfs_get_tree+0x29/0xd0 vfs_cmd_create+0x59/0xe0 __do_sys_fsconfig+0x4f6/0x6b0 do_syscall_64+0x50/0x1f0 entry_SYSCALL_64_after_hwframe+0x76/0x7e ================================================================== This issue can be reproduced using the following commands: mkfs.ext4 -F -q -b 1024 /dev/sda 5G tune2fs -O quota,project /dev/sda mount /dev/sda /tmp/test With DOUBLE_CHECK defined, mb_group_bb_bitmap_alloc() reads and validates the block bitmap. When the validation fails, ext4_mark_group_bitmap_corrupted() attempts to update sbi->s_freeclusters_counter. However, this percpu_counter has not been initialized yet at this point, which leads to the panic described above. Fix this by moving the execution of ext4_percpu_param_init() to occur before ext4_mb_init(), ensuring the per-CPU counters are initialized before they are used.

Why

The product uses or accesses a resource that has not been initialized.

How

An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

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 → Use of Uninitialized Resource → cause the confidentiality, integrity or availability impact described by the vendor
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-908 ↗

CWE-908: Use of Uninitialized Resource. The product uses or accesses a resource that has not been initialized.

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.
CWE-908
A

Official authority intelligence

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

ENISA EUVD · EUVD-2026-28558Official EUVD mapping

In the Linux kernel, the following vulnerability has been resolved: ext4: move ext4_percpu_param_init() before ext4_mb_init() When running `kvm-xfstests -c ext4/1k -C 1 generic/383` with the `DOUBLE_CHECK` macro defined, the following panic is triggered: ================================================================== EXT4-fs error (device vdc): ext4_validate_block_bitmap:423: comm mount: bg 0: bad block bitmap checksum BUG: unable to handle page fault for address: ff110000fa2cc000 PGD 3e01067 P4D 3e02067 PUD 0 Oops: Oops: 0000 [#1] SMP NOPTI CPU: 0 UID: 0 PID: 2386 Comm: mount Tainted: G W 6.18.0-gba65a4e7120a-dirty #1152 PREEMPT(none) RIP: 0010:percpu_counter_add_batch+0x13/0xa0 Call Trace: <TASK> ext4_mark_group_bitmap_corrupted+0xcb/0xe0 ext4_validate_block_bitmap+0x2a1/0x2f0 ext4_read_block_bitmap+0x33/0x50 mb_group_bb_bitmap_alloc+0x33/0x80 ext4_mb_add_groupinfo+0x190/0x250 ext4_mb_init_backend+0x87/0x290 ext4_mb_init+0x456/0x640 __ext4_fill_super+0x1072/0x1680 ext4_fill_super+0xd3/0x280 get_tree_bdev_flags+0x132/0x1d0 vfs_get_tree+0x29/0xd0 vfs_cmd_create+0x59/0xe0 __do_sys_fsconfig+0x4f6/0x6b0 do_syscall_64+0x50/0x1f0 entry_SYSCALL_64_after_hwframe+0x76/0x7e ================================================================== This issue can be reproduced using the following commands: mkfs.ext4 -F -q -b 1024 /dev/sda 5G tune2fs -O quota,project /dev/sda mount /dev/sda /tmp/test With DOUBLE_CHECK defined, mb_group_bb_bitmap_alloc() reads and validates the block bitmap. When the validation fails, ext4_mark_group_bitmap_corrupted() attempts to update sbi->s_freeclusters_counter. However, this percpu_counter has not been initialized yet at this point, which leads to the panic described above. Fix this by moving the execution of ext4_percpu_param_init() to occur before ext4_mb_init(), ensuring the per-CPU counters are initialized before they are used.

Official EUVD record ↗
BSI · German · WID-SEC-2026-1454Linux Kernel: Mehrere Schwachstellen

Ein Angreifer kann mehrere Schwachstellen im Linux Kernel ausnutzen, um einen nicht näher spezifizierten Angriff durchzuführen, möglicherweise Sicherheitsmaßnahmen zu umgehen, Daten zu manipulieren oder offenzulegen oder einen Denial-of-Service-Zustand zu verursachen.

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

d?id=CVE-2026-43273 Référence CVE CVE-2026-43275 https://www.cve.org/CVERecord?id=CVE-2026-43275 Référence CVE CVE-2026-43277 https://www.cve.org/CVERecord?id=CVE-2026-43277 Référence CVE CVE-2026-43278 https://www.cve.org/CVERecord?id=CVE-2026-43278 Référence CVE CVE-2026-43279 https://www.cve.org/CVERecord?id=CVE-2026-43279 Référence CVE CVE-2026-43281 https://www.cve.org/CVERecord?id=CVE-2026-43281 Référence CVE CVE-2026-43283 https://www.cve.org/CVERecord?id=CVE-2026-43283 Référence CVE CVE-2026-43284 https://www.cve.org/CVERecord?id=CVE-2026-43284 Référence CVE CVE-2026-43287 https://www.cve.org/CVERecord?id=CVE-2026-43287 Référence CVE CVE-2026-43288 https://www.cve.org/CVERecord?id=CVE-2026-43288 Référence CVE CVE-2026-43289 https://www.cve.org/CVERecord?id=CVE-2026-43289 Référence CVE CVE-2026-43291 https://www.cve.org/CVERecord?id=CVE-2026-43291 Référence CVE CVE-2026-43295 https://www.cve.org/CVERecord?id=CVE-2026-43295 Référence CVE CVE-2026-43296 https://www.cve.org/CVERecord?id=CVE-2026-43296 Référence CVE CVE-2026-43297 https://www.cve.org/CVERecord?id=CVE-2026-43297 Référence CVE CVE-2026-43300 https://www.cve.org/CVERecord?id=CVE-2026-43300 Référence CVE CVE-2026-43302 https://www.cve.org/CVERecord?id=CVE-2026-43302 Référence CVE CVE-2026-43304 https://www.cve.org/CVERecord?id=

Official advisory ↗
CERT-FR · French · CERTFR-2026-AVI-0861Multiples vulnérabilités dans le noyau Linux d'Ubuntu

d?id=CVE-2026-43271 Référence CVE CVE-2026-43273 https://www.cve.org/CVERecord?id=CVE-2026-43273 Référence CVE CVE-2026-43275 https://www.cve.org/CVERecord?id=CVE-2026-43275 Référence CVE CVE-2026-43277 https://www.cve.org/CVERecord?id=CVE-2026-43277 Référence CVE CVE-2026-43278 https://www.cve.org/CVERecord?id=CVE-2026-43278 Référence CVE CVE-2026-43279 https://www.cve.org/CVERecord?id=CVE-2026-43279 Référence CVE CVE-2026-43283 https://www.cve.org/CVERecord?id=CVE-2026-43283 Référence CVE CVE-2026-43284 https://www.cve.org/CVERecord?id=CVE-2026-43284 Référence CVE CVE-2026-43287 https://www.cve.org/CVERecord?id=CVE-2026-43287 Référence CVE CVE-2026-43288 https://www.cve.org/CVERecord?id=CVE-2026-43288 Référence CVE CVE-2026-43289 https://www.cve.org/CVERecord?id=CVE-2026-43289 Référence CVE CVE-2026-43291 https://www.cve.org/CVERecord?id=CVE-2026-43291 Référence CVE CVE-2026-43295 https://www.cve.org/CVERecord?id=CVE-2026-43295 Référence CVE CVE-2026-43296 https://www.cve.org/CVERecord?id=CVE-2026-43296 Référence CVE CVE-2026-43297 https://www.cve.org/CVERecord?id=CVE-2026-43297 Référence CVE CVE-2026-43300 https://www.cve.org/CVERecord?id=CVE-2026-43300 Référence CVE CVE-2026-43302 https://www.cve.org/CVERecord?id=CVE-2026-43302 Référence CVE CVE-2026-43304 https://www.cve.org/CVERecord?id=

Official advisory ↗
CERT-FR · French · CERTFR-2026-AVI-0831Multiples vulnérabilités dans le noyau Linux d'Ubuntu

d?id=CVE-2026-43271 Référence CVE CVE-2026-43273 https://www.cve.org/CVERecord?id=CVE-2026-43273 Référence CVE CVE-2026-43275 https://www.cve.org/CVERecord?id=CVE-2026-43275 Référence CVE CVE-2026-43277 https://www.cve.org/CVERecord?id=CVE-2026-43277 Référence CVE CVE-2026-43278 https://www.cve.org/CVERecord?id=CVE-2026-43278 Référence CVE CVE-2026-43279 https://www.cve.org/CVERecord?id=CVE-2026-43279 Référence CVE CVE-2026-43283 https://www.cve.org/CVERecord?id=CVE-2026-43283 Référence CVE CVE-2026-43284 https://www.cve.org/CVERecord?id=CVE-2026-43284 Référence CVE CVE-2026-43287 https://www.cve.org/CVERecord?id=CVE-2026-43287 Référence CVE CVE-2026-43288 https://www.cve.org/CVERecord?id=CVE-2026-43288 Référence CVE CVE-2026-43289 https://www.cve.org/CVERecord?id=CVE-2026-43289 Référence CVE CVE-2026-43291 https://www.cve.org/CVERecord?id=CVE-2026-43291 Référence CVE CVE-2026-43295 https://www.cve.org/CVERecord?id=CVE-2026-43295 Référence CVE CVE-2026-43296 https://www.cve.org/CVERecord?id=CVE-2026-43296 Référence CVE CVE-2026-43297 https://www.cve.org/CVERecord?id=CVE-2026-43297 Référence CVE CVE-2026-43300 https://www.cve.org/CVERecord?id=CVE-2026-43300 Référence CVE CVE-2026-43302 https://www.cve.org/CVERecord?id=CVE-2026-43302 Référence CVE CVE-2026-43304 https://www.cve.org/CVERecord?id=

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2026-015897LinuxのLinux Kernelにおける初期化されていないリソースの使用に関する脆弱性

Linuxカーネルに存在した脆弱性が修正されました。この問題は、ext4ファイルシステムにおいてext4_mb_init()の前にext4_percpu_param_init()を移動することで解決されています。`DOUBLE_CHECK`マクロが定義された状態で`kvm-xfstests -c ext4/1k -C 1 generic/383`を実行すると、次のようなパニックが発生しました:EXT4-fsエラー(デバイスvdc):ext4_validate_block_bitmap:423:comm mount:bg 0:ブロックビットマップのチェックサム不良が起きました。BUG: アドレスff110000fa2cc000に対するページフォルトを処理できませんでした。PGD 3e01067 P4D 3e02067 PUD 0。Oops: 0000 [#1] SMP NOPTICPU: 0 UID: 0 PID: 2386 Comm: mount Tainted: G W 6.18.0-gba65a4e7120a-dirty #1152 PREEMPT(none) RIP: 0010:percpu_counter_add_batch+0x13/0xa0 呼び出しトレースは、ext4_mark_group_bitmap_corrupted+0xcb/0xe0、ext4_validate_block_bitmap+0x2a1/0x2f0、ext4_read_block_bitmap+0x33/0x50、mb_group_bb_bitmap_alloc+0x33/0x80、ext4_mb_add_groupinfo+0x190/0x250、ext4_mb_init_backend+0x87/0x290、ext4_mb_init+0x456/0x640、__ext4_fill_super+0x1072/0x1680、ext4_fill_super+0xd3/0x280、get_tree_bdev_flags+0x132/0x1d0、vfs_get_tree+0x29/0xd0、vfs_cmd_create+0x59/0xe0、__do_sys_fsconfig+0x4f6/0x6b0、do_syscall_64+0x50/0x1f0、entry_SYSCALL_64_after_hwframe+0x76/0x7eとなっています。この問題は、以下のコマンドで再現できます。mkfs.ext4 -F -q -b 1024 /dev/sda 5G、tune2fs -O quota,project /dev/sda、mount /dev/sda /tmp/test。DOUBLE_CHECKが定義された場合、mb_group_bb_bitmap_alloc()はブロックビットマップを読み取り検証します。検証に失敗するとext4_mark_group_bitmap_corrupted()がsbi-s_freeclusters_counterを更新しようとしますが、この時点でpercpu_counterがまだ初期化されていないため、パニックが発生していました。対応として、ext4_percpu_param_init()をext4_mb_init()の前に移動し、使用前にper-CPUカウンタが確実に初期化されるようにしました。

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.
Fix availability varies by product
Affected
Linux: patch: 7.0, d5e03cbb0c88cd1be39f2adc37d602230045964b < 0d5fcb063cdabb9aeaa8554b7fedad2092c4150e, d5e03cbb0c88cd1be39f2adc37d602230045964b < 0b3d80c56957862ba477ca0ce30c12cad9179c2b, d5e03cbb0c88cd1be39f2adc37d602230045964b < bf5b609524497c195f801cd5707252384aed8149, patch: 6.6.128, patch: 0, d5e03cbb0c88cd1be39f2adc37d602230045964b < aec095f3cc6cf209effd93278ce35be27db81d73, patch: 6.1.188, 3.17, patch: 6.19.6, d5e03cbb0c88cd1be39f2adc37d602230045964b < 9e9fb259bcddf459a0168f4a964e979e500a68a5, patch: 6.12.75, patch: 6.18.16, d5e03cbb0c88cd1be39f2adc37d602230045964b < 270564513489d98b721a1e4a10017978d5213bff
Fixed
Linux: < 3.17, 6.1.188 ≤ 6.1.*, 6.6.128 ≤ 6.6.*, 6.12.75 ≤ 6.12.*, 6.18.16 ≤ 6.18.*, 6.19.6 ≤ 6.19.*, 7.0 ≤ *
Action
Use the product-specific evidence above. Patch only products with a verified fixed release, and keep every affected or under-investigation state without a matching fix in the remediation queue.
Workaround
No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.
04

Evidence and provenance

Published 8 May 2026 · Last source change 14 Sept 2026, 11:58 UTC · CWE-908 · Use of Uninitialized Resource

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-2026-28558
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceNIST NVD
NVD statusNVD modified after enrichment

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

Material change intelligence

What changed after publication

View recent updates ↗
  1. Affected versionsThe structured affected or fixed version information changed.
    Before
    d5e03cbb0c88cd1be39f2adc37d602230045964b < 0d5fcb063cdabb9aeaa8554b7fedad2092c4150e; d5e03cbb0c88cd1be39f2adc37d602230045964b < 9e9fb259bcddf459a0168f4a964e979e500a68a5; d5e03cbb0c88cd1be39f2adc37d602230045964b < bf5b609524497c195f801cd5707252384aed8149; d5e03cbb0c88cd1be39f2adc37d602230045964b < aec095f3cc6cf209effd93278ce35be27db81d73; d5e03cbb0c88cd1be39f2adc37d602230045964b < 270564513489d98b721a1e4a10017978d5213bff; 3.17 · Fixed: < 3.17; 6.6.128 ≤ 6.6.*; 6.12.75 ≤ 6.12.*; 6.18.16 ≤ 6.18.*; 6.19.6 ≤ 6.19.*; 7.0 ≤ *
    After
    Linux: d5e03cbb0c88cd1be39f2adc37d602230045964b < 0b3d80c56957862ba477ca0ce30c12cad9179c2b, d5e03cbb0c88cd1be39f2adc37d602230045964b < 0d5fcb063cdabb9aeaa8554b7fedad2092c4150e, d5e03cbb0c88cd1be39f2adc37d602230045964b < 9e9fb259bcddf459a0168f4a964e979e500a68a5, d5e03cbb0c88cd1be39f2adc37d602230045964b < bf5b609524497c195f801cd5707252384aed8149, d5e03cbb0c88cd1be39f2adc37d602230045964b < aec095f3cc6cf209effd93278ce35be27db81d73, d5e03cbb0c88cd1be39f2adc37d602230045964b < 270564513489d98b721a1e4a10017978d5213bff, 3.17 · Fixed: Linux: < 3.17, 6.1.188 ≤ 6.1.*, 6.6.128 ≤ 6.6.*, 6.12.75 ≤ 6.12.*, 6.18.16 ≤ 6.18.*, 6.19.6 ≤ 6.19.*, 7.0 ≤ *
    CNA ↗
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-2026-43288 · cve.blacktree.nl