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Full vulnerability report · 2025
CVE-2023-54271High confidence

blk-cgroup: Fix NULL deref caused by blkg_policy_data being installed before init

Linux · Linux

…UnscoredAssess manually
Recommended action
Patch only the product branches with a verified fix

No CVSS base score is available from the CNA, CISA ADP or NIST. Absence of a score is not evidence of low risk; review the vendor advisory, affected exposure and exploit evidence. Verified remediation exists for at least one product or source, but 9 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 severityUnscoredOperational priority:Needs assessment, manual assessment needed.unscored

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • EPSS is 0.20% 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: Manual assessmentRemediation target: Manual assessment

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 9 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.

13 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 9 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.6.5.3-1Debian Security Tracker ↗Source updated 6 Oct 2026
Debian bookwormbookworm · sourcelinuxVendor fix publishedDebian records a fixed source-package version for this release.6.1.176-1Debian Security Tracker ↗Source updated 6 Oct 2026
Debian forkyforky · sourcelinuxVendor fix publishedDebian records a fixed source-package version for this release.6.5.3-1Debian Security Tracker ↗Source updated 6 Oct 2026
Debian sidsid · sourcelinuxVendor fix publishedDebian records a fixed source-package version for this release.6.5.3-1Debian Security Tracker ↗Source updated 6 Oct 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 Ubuntu Security ↗Source updated 5 Oct 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 Ubuntu Security ↗Source updated 5 Oct 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 Ubuntu Security ↗Source updated 5 Oct 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 Ubuntu Security ↗Source updated 5 Oct 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 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-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
Direct vendor intelligence

Authoritative vendor CSAF and VEX advisories

Structured product status and remediation from the issuing vendor. Product-state explanations are always visible; large lists can be searched or downloaded.

1 current
CVE-2023-54271 · CSAF 2.0 · revision 39 · interimSUSE Product Security TeamCVE-2023-54271
88 known affected

The vendor explicitly identifies these products as affected by this CVE.

  • kernel-default as component of SLES-LTSS-TERADATA 15 SP2
  • kernel-source as component of SLES-LTSS-TERADATA 15 SP2
  • cluster-md-kmp-default as component of SUSE Linux Enterprise High Availability Extension 15 SP3
  • dlm-kmp-default as component of SUSE Linux Enterprise High Availability Extension 15 SP3
  • gfs2-kmp-default as component of SUSE Linux Enterprise High Availability Extension 15 SP3
  • kernel-default as component of SUSE Linux Enterprise High Availability Extension 15 SP3
  • kernel-source as component of SUSE Linux Enterprise High Availability Extension 15 SP3
  • ocfs2-kmp-default as component of SUSE Linux Enterprise High Availability Extension 15 SP3
  • kernel-default as component of SUSE Linux Enterprise High Performance Computing 15 SP2
  • kernel-default-devel as component of SUSE Linux Enterprise High Performance Computing 15 SP2
  • kernel-devel as component of SUSE Linux Enterprise High Performance Computing 15 SP2
  • kernel-macros as component of SUSE Linux Enterprise High Performance Computing 15 SP2
Summary
In the Linux kernel, the following vulnerability has been resolved: blk-cgroup: Fix NULL deref caused by blkg_policy_data being installed before init blk-iocost sometimes causes the following crash: BUG: kernel NULL pointer dereference, address: 00000000000000e0 ... RIP: 0010:_raw_spin_lock+0x17/0x30 Code: be 01 02 00 00 e8 79 38 39 ff 31 d2 89 d0 5d c3 0f 1f 00 0f 1f 44 00 00 55 48 89 e5 65 ff 05 48 d0 34 7e b9 01 00 00 00 31 c0 0f b1 0f 75 02 5d c3 89 c6 e8 ea 04 00 00 5d c3 0f 1f 84 00 00 RSP: 0018:ffffc900023b3d40 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 00000000000000e0 RCX: 0000000000000001 RDX: ffffc900023b3d20 RSI: ffffc900023b3cf0 RDI: 00000000000000e0 RBP: ffffc900023b3d40 R08: ffffc900023b3c10 R09: 0000000000000003 R10: 0000000000000064 R11: 000000000000000a R12: ffff888102337000 R13: fffffffffffffff2 R14: ffff88810af408c8 R15: ffff8881070c3600 FS: 00007faaaf364fc0(0000) GS:ffff88842fdc0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000000000e0 CR3: 00000001097b1000 CR4: 0000000000350ea0 Call Trace: ioc_weight_write+0x13d/0x410 cgroup_file_write+0x7a/0x130 kernfs_fop_write_iter+0xf5/0x170 vfs_write+0x298/0x370 ksys_write+0x5f/0xb0 __x64_sys_write+0x1b/0x20 do_syscall_64+0x3d/0x80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 This happens because iocg->ioc is NULL. The field is initialized by ioc_pd_init() and never cleared. The NULL deref is caused by blkcg_activate_policy() installing blkg_policy_data before initializing it. blkcg_activate_policy() was doing the following: 1. Allocate pd's for all existing blkg's and install them in blkg->pd[]. 2. Initialize all pd's. 3. Online all pd's. blkcg_activate_policy() only grabs the queue_lock and may release and re-acquire the lock as allocation may need to sleep. ioc_weight_write() grabs blkcg->lock and iterates all its blkg's. The two can race and if ioc_weight_write() runs during #1 or between #1 and #2, it can encounter a pd which is not initialized yet, leading to crash. The crash can be reproduced with the following script: #!/bin/bash echo +io > /sys/fs/cgroup/cgroup.subtree_control systemd-run --unit touch-sda --scope dd if=/dev/sda of=/dev/null bs=1M count=1 iflag=direct echo 100 > /sys/fs/cgroup/system.slice/io.weight bash -c "echo '8:0 enable=1' > /sys/fs/cgroup/io.cost.qos" & sleep .2 echo 100 > /sys/fs/cgroup/system.slice/io.weight with the following patch applied: > diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c > index fc49be622e05..38d671d5e10c 100644 > --- a/block/blk-cgroup.c > +++ b/block/blk-cgroup.c > @@ -1553,6 +1553,12 @@ int blkcg_activate_policy(struct gendisk *disk, const struct blkcg_policy *pol) > pd->online = false; > } > > + if (system_state == SYSTEM_RUNNING) { > + spin_unlock_irq(&q->queue_lock); > + ssleep(1); > + spin_lock_irq(&q->queue_lock); > + } > + > /* all allocated, init in the same order */ > if (pol->pd_init_fn) > list_for_each_entry_reverse(blkg, &q->blkg_list, q_node) I don't see a reason why all pd's should be allocated, initialized and onlined together. The only ordering requirement is that parent blkgs to be initialized and onlined before children, which is guaranteed from the walking order. Let's fix the bug by allocating, initializing and onlining pd for each blkg and holding blkcg->lock over initialization and onlining. This ensures that an installed blkg is always fully initialized and onlined removing the the race window.
Remediation
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
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-2023-60370

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 actionPatch only the product branches with a verified fix

No CVSS base score is available from the CNA, CISA ADP or NIST. Absence of a score is not evidence of low risk; review the vendor advisory, affected exposure and exploit evidence. Verified remediation exists for at least one product or source, but 9 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: blk-cgroup: Fix NULL deref caused by blkg_policy_data being installed before init blk-iocost sometimes causes the following crash: BUG: kernel NULL pointer dereference, address: 00000000000000e0 ... RIP: 0010:_raw_spin_lock+0x17/0x30 Code: be 01 02 00 00 e8 79 38 39 ff 31 d2 89 d0 5d c3 0f 1f 00 0f 1f 44 00 00 55 48 89 e5 65 ff 05 48 d0 34 7e b9 01 00 00 00 31 c0 <f0> 0f b1 0f 75 02 5d c3 89 c6 e8 ea 04 00 00 5d c3 0f 1f 84 00 00 RSP: 0018:ffffc900023b3d40 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 00000000000000e0 RCX: 0000000000000001 RDX: ffffc900023b3d20 RSI: ffffc900023b3cf0 RDI: 00000000000000e0 RBP: ffffc900023b3d40 R08: ffffc900023b3c10 R09: 0000000000000003 R10: 0000000000000064 R11: 000000000000000a R12: ffff888102337000 R13: fffffffffffffff2 R14: ffff88810af408c8 R15: ffff8881070c3600 FS: 00007faaaf364fc0(0000) GS:ffff88842fdc0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000000000e0 CR3: 00000001097b1000 CR4: 0000000000350ea0 Call Trace: <TASK> ioc_weight_write+0x13d/0x410 cgroup_file_write+0x7a/0x130 kernfs_fop_write_iter+0xf5/0x170 vfs_write+0x298/0x370 ksys_write+0x5f/0xb0 __x64_sys_write+0x1b/0x20 do_syscall_64+0x3d/0x80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 This happens because iocg->ioc is NULL. The field is initialized by ioc_pd_init() and never cleared. The NULL deref is caused by blkcg_activate_policy() installing blkg_policy_data before initializing it. blkcg_activate_policy() was doing the following: 1. Allocate pd's for all existing blkg's and install them in blkg->pd[]. 2. Initialize all pd's. 3. Online all pd's. blkcg_activate_policy() only grabs the queue_lock and may release and re-acquire the lock as allocation may need to sleep. ioc_weight_write() grabs blkcg->lock and iterates all its blkg's. The two can race and if ioc_weight_write() runs during #1 or between #1 and #2, it can encounter a pd which is not initialized yet, leading to crash. The crash can be reproduced with the following script: #!/bin/bash echo +io > /sys/fs/cgroup/cgroup.subtree_control systemd-run --unit touch-sda --scope dd if=/dev/sda of=/dev/null bs=1M count=1 iflag=direct echo 100 > /sys/fs/cgroup/system.slice/io.weight bash -c "echo '8:0 enable=1' > /sys/fs/cgroup/io.cost.qos" & sleep .2 echo 100 > /sys/fs/cgroup/system.slice/io.weight with the following patch applied: > diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c > index fc49be622e05..38d671d5e10c 100644 > --- a/block/blk-cgroup.c > +++ b/block/blk-cgroup.c > @@ -1553,6 +1553,12 @@ int blkcg_activate_policy(struct gendisk *disk, const struct blkcg_policy *pol) > pd->online = false; > } > > + if (system_state == SYSTEM_RUNNING) { > + spin_unlock_irq(&q->queue_lock); > + ssleep(1); > + spin_lock_irq(&q->queue_lock); > + } > + > /* all allocated, init in the same order */ > if (pol->pd_init_fn) > list_for_each_entry_reverse(blkg, &q->blkg_list, q_node) I don't see a reason why all pd's should be allocated, initialized and onlined together. The only ordering requirement is that parent blkgs to be initialized and onlined before children, which is guaranteed from the walking order. Let's fix the bug by allocating, initializing and onlining pd for each blkg and holding blkcg->lock over initialization and onlining. This ensures that an installed blkg is always fully initialized and onlined removing the the race window.

What

In the Linux kernel, the following vulnerability has been resolved: blk-cgroup: Fix NULL deref caused by blkg_policy_data being installed before init blk-iocost sometimes causes the following crash: BUG: kernel NULL pointer dereference, address: 00000000000000e0 ... RIP: 0010:_raw_spin_lock+0x17/0x30 Code: be 01 02 00 00 e8 79 38 39 ff 31 d2 89 d0 5d c3 0f 1f 00 0f 1f 44 00 00 55 48 89 e5 65 ff 05 48 d0 34 7e b9 01 00 00 00 31 c0 <f0> 0f b1 0f 75 02 5d c3 89 c6 e8 ea 04 00 00 5d c3 0f 1f 84 00 00 RSP: 0018:ffffc900023b3d40 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 00000000000000e0 RCX: 0000000000000001 RDX: ffffc900023b3d20 RSI: ffffc900023b3cf0 RDI: 00000000000000e0 RBP: ffffc900023b3d40 R08: ffffc900023b3c10 R09: 0000000000000003 R10: 0000000000000064 R11: 000000000000000a R12: ffff888102337000 R13: fffffffffffffff2 R14: ffff88810af408c8 R15: ffff8881070c3600 FS: 00007faaaf364fc0(0000) GS:ffff88842fdc0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000000000e0 CR3: 00000001097b1000 CR4: 0000000000350ea0 Call Trace: <TASK> ioc_weight_write+0x13d/0x410 cgroup_file_write+0x7a/0x130 kernfs_fop_write_iter+0xf5/0x170 vfs_write+0x298/0x370 ksys_write+0x5f/0xb0 __x64_sys_write+0x1b/0x20 do_syscall_64+0x3d/0x80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 This happens because iocg->ioc is NULL. The field is initialized by ioc_pd_init() and never cleared. The NULL deref is caused by blkcg_activate_policy() installing blkg_policy_data before initializing it. blkcg_activate_policy() was doing the following: 1. Allocate pd's for all existing blkg's and install them in blkg->pd[]. 2. Initialize all pd's. 3. Online all pd's. blkcg_activate_policy() only grabs the queue_lock and may release and re-acquire the lock as allocation may need to sleep. ioc_weight_write() grabs blkcg->lock and iterates all its blkg's. The two can race and if ioc_weight_write() runs during #1 or between #1 and #2, it can encounter a pd which is not initialized yet, leading to crash. The crash can be reproduced with the following script: #!/bin/bash echo +io > /sys/fs/cgroup/cgroup.subtree_control systemd-run --unit touch-sda --scope dd if=/dev/sda of=/dev/null bs=1M count=1 iflag=direct echo 100 > /sys/fs/cgroup/system.slice/io.weight bash -c "echo '8:0 enable=1' > /sys/fs/cgroup/io.cost.qos" & sleep .2 echo 100 > /sys/fs/cgroup/system.slice/io.weight with the following patch applied: > diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c > index fc49be622e05..38d671d5e10c 100644 > --- a/block/blk-cgroup.c > +++ b/block/blk-cgroup.c > @@ -1553,6 +1553,12 @@ int blkcg_activate_policy(struct gendisk *disk, const struct blkcg_policy *pol) > pd->online = false; > } > > + if (system_state == SYSTEM_RUNNING) { > + spin_unlock_irq(&q->queue_lock); > + ssleep(1); > + spin_lock_irq(&q->queue_lock); > + } > + > /* all allocated, init in the same order */ > if (pol->pd_init_fn) > list_for_each_entry_reverse(blkg, &q->blkg_list, q_node) I don't see a reason why all pd's should be allocated, initialized and onlined together. The only ordering requirement is that parent blkgs to be initialized and onlined before children, which is guaranteed from the walking order. Let's fix the bug by allocating, initializing and onlining pd for each blkg and holding blkcg->lock over initialization and onlining. This ensures that an installed blkg is always fully initialized and onlined removing the the race window.

Why

The current structured CVE record identifies a security weakness, but the root cause requires confirmation in the linked vendor material.

How

An attacker operating through the affected interface may attempt exploitation when the stated preconditions are met. If successful, the issue may disrupt the affected service.

What

In the Linux kernel, the following vulnerability has been resolved: blk-cgroup: Fix NULL deref caused by blkg_policy_data being installed before init blk-iocost sometimes causes the following crash: BUG: kernel NULL pointer dereference, address: 00000000000000e0 ... RIP: 0010:_raw_spin_lock+0x17/0x30 Code: be 01 02 00 00 e8 79 38 39 ff 31 d2 89 d0 5d c3 0f 1f 00 0f 1f 44 00 00 55 48 89 e5 65 ff 05 48 d0 34 7e b9 01 00 00 00 31 c0 <f0> 0f b1 0f 75 02 5d c3 89 c6 e8 ea 04 00 00 5d c3 0f 1f 84 00 00 RSP: 0018:ffffc900023b3d40 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 00000000000000e0 RCX: 0000000000000001 RDX: ffffc900023b3d20 RSI: ffffc900023b3cf0 RDI: 00000000000000e0 RBP: ffffc900023b3d40 R08: ffffc900023b3c10 R09: 0000000000000003 R10: 0000000000000064 R11: 000000000000000a R12: ffff888102337000 R13: fffffffffffffff2 R14: ffff88810af408c8 R15: ffff8881070c3600 FS: 00007faaaf364fc0(0000) GS:ffff88842fdc0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000000000e0 CR3: 00000001097b1000 CR4: 0000000000350ea0 Call Trace: <TASK> ioc_weight_write+0x13d/0x410 cgroup_file_write+0x7a/0x130 kernfs_fop_write_iter+0xf5/0x170 vfs_write+0x298/0x370 ksys_write+0x5f/0xb0 __x64_sys_write+0x1b/0x20 do_syscall_64+0x3d/0x80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 This happens because iocg->ioc is NULL. The field is initialized by ioc_pd_init() and never cleared. The NULL deref is caused by blkcg_activate_policy() installing blkg_policy_data before initializing it. blkcg_activate_policy() was doing the following: 1. Allocate pd's for all existing blkg's and install them in blkg->pd[]. 2. Initialize all pd's. 3. Online all pd's. blkcg_activate_policy() only grabs the queue_lock and may release and re-acquire the lock as allocation may need to sleep. ioc_weight_write() grabs blkcg->lock and iterates all its blkg's. The two can race and if ioc_weight_write() runs during #1 or between #1 and #2, it can encounter a pd which is not initialized yet, leading to crash. The crash can be reproduced with the following script: #!/bin/bash echo +io > /sys/fs/cgroup/cgroup.subtree_control systemd-run --unit touch-sda --scope dd if=/dev/sda of=/dev/null bs=1M count=1 iflag=direct echo 100 > /sys/fs/cgroup/system.slice/io.weight bash -c "echo '8:0 enable=1' > /sys/fs/cgroup/io.cost.qos" & sleep .2 echo 100 > /sys/fs/cgroup/system.slice/io.weight with the following patch applied: > diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c > index fc49be622e05..38d671d5e10c 100644 > --- a/block/blk-cgroup.c > +++ b/block/blk-cgroup.c > @@ -1553,6 +1553,12 @@ int blkcg_activate_policy(struct gendisk *disk, const struct blkcg_policy *pol) > pd->online = false; > } > > + if (system_state == SYSTEM_RUNNING) { > + spin_unlock_irq(&q->queue_lock); > + ssleep(1); > + spin_lock_irq(&q->queue_lock); > + } > + > /* all allocated, init in the same order */ > if (pol->pd_init_fn) > list_for_each_entry_reverse(blkg, &q->blkg_list, q_node) I don't see a reason why all pd's should be allocated, initialized and onlined together. The only ordering requirement is that parent blkgs to be initialized and onlined before children, which is guaranteed from the walking order. Let's fix the bug by allocating, initializing and onlining pd for each blkg and holding blkcg->lock over initialization and onlining. This ensures that an installed blkg is always fully initialized and onlined removing the the race window.

Why

The current structured CVE record identifies a security weakness, but the root cause requires confirmation in the linked vendor material.

How

An attacker operating through the affected interface may attempt exploitation when the stated preconditions are met. 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
the affected interface → vulnerable operation → disrupt the affected service
Attack surface
Unspecified
Privileges required
Not stated in the selected CVSS metric
User interaction
Not stated in the selected CVSS metric
Attack complexity
Not stated in the selected CVSS metric
Security boundary
Not stated in the selected CVSS metric
Weakness
?CWE means Common Weakness Enumeration.
CWE not yet assigned
CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
Not available from the selected scoring authority.
Post-exploitation / living off the land
No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
Denial of service
A

Official authority intelligence

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

BSI · German · WID-SEC-2025-2941Linux Kernel: Mehrere Schwachstellen ermöglichen Denial of Service

Ein Angreifer kann diese Schwachstellen ausnutzen, um nicht näher spezifizierte Angriffe durchzuführen, die möglicherweise zu Denial‑of‑Service, Speicherbeschädigung oder weiteren nicht definierten Auswirkungen führen.

Official advisory ↗
Cyber Security Agency of Singapore · English · CSA-SB-20251231Security Bulletin 31 Dec 2025

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 31 Dec 2025, published on 31 December 2025. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗
CERT-FR · French · CERTFR-2026-AVI-0862Multiples vulnérabilités dans le noyau Linux de Debian LTS

d?id=CVE-2022-50493 Référence CVE CVE-2022-50552 https://www.cve.org/CVERecord?id=CVE-2022-50552 Référence CVE CVE-2023-53133 https://www.cve.org/CVERecord?id=CVE-2023-53133 Référence CVE CVE-2023-53292 https://www.cve.org/CVERecord?id=CVE-2023-53292 Référence CVE CVE-2023-53421 https://www.cve.org/CVERecord?id=CVE-2023-53421 Référence CVE CVE-2023-53596 https://www.cve.org/CVERecord?id=CVE-2023-53596 Référence CVE CVE-2023-53989 https://www.cve.org/CVERecord?id=CVE-2023-53989 Référence CVE CVE-2023-54125 https://www.cve.org/CVERecord?id=CVE-2023-54125 Référence CVE CVE-2023-54129 https://www.cve.org/CVERecord?id=CVE-2023-54129 Référence CVE CVE-2023-54271 https://www.cve.org/CVERecord?id=CVE-2023-54271 Référence CVE CVE-2023-54322 https://www.cve.org/CVERecord?id=CVE-2023-54322 Référence CVE CVE-2024-27012 https://www.cve.org/CVERecord?id=CVE-2024-27012 Référence CVE CVE-2024-36922 https://www.cve.org/CVERecord?id=CVE-2024-36922 Référence CVE CVE-2024-43902 https://www.cve.org/CVERecord?id=CVE-2024-43902 Référence CVE CVE-2024-53221 https://www.cve.org/CVERecord?id=CVE-2024-53221 Référence CVE CVE-2024-56657 https://www.cve.org/CVERecord?id=CVE-2024-56657 Référence CVE CVE-2025-10263 https://www.cve.org/CVERecord?id=CVE-2025-10263 Référence CVE CVE-2025-21739 https://www.cve.org/CVERecord?id=

Official advisory ↗
CERT-FR · French · CERTFR-2026-AVI-0369Multiples vulnérabilités dans le noyau Linux de SUSE

d?id=CVE-2023-54253 Référence CVE CVE-2023-54254 https://www.cve.org/CVERecord?id=CVE-2023-54254 Référence CVE CVE-2023-54255 https://www.cve.org/CVERecord?id=CVE-2023-54255 Référence CVE CVE-2023-54258 https://www.cve.org/CVERecord?id=CVE-2023-54258 Référence CVE CVE-2023-54261 https://www.cve.org/CVERecord?id=CVE-2023-54261 Référence CVE CVE-2023-54263 https://www.cve.org/CVERecord?id=CVE-2023-54263 Référence CVE CVE-2023-54264 https://www.cve.org/CVERecord?id=CVE-2023-54264 Référence CVE CVE-2023-54266 https://www.cve.org/CVERecord?id=CVE-2023-54266 Référence CVE CVE-2023-54267 https://www.cve.org/CVERecord?id=CVE-2023-54267 Référence CVE CVE-2023-54271 https://www.cve.org/CVERecord?id=CVE-2023-54271 Référence CVE CVE-2023-54276 https://www.cve.org/CVERecord?id=CVE-2023-54276 Référence CVE CVE-2023-54278 https://www.cve.org/CVERecord?id=CVE-2023-54278 Référence CVE CVE-2023-54281 https://www.cve.org/CVERecord?id=CVE-2023-54281 Référence CVE CVE-2023-54282 https://www.cve.org/CVERecord?id=CVE-2023-54282 Référence CVE CVE-2023-54283 https://www.cve.org/CVERecord?id=CVE-2023-54283 Référence CVE CVE-2023-54285 https://www.cve.org/CVERecord?id=CVE-2023-54285 Référence CVE CVE-2023-54289 https://www.cve.org/CVERecord?id=CVE-2023-54289 Référence CVE CVE-2023-54291 https://www.cve.org/CVERecord?id=

Official advisory ↗
CERT-FR · French · CERTFR-2026-AVI-0326Multiples vulnérabilités dans les produits VMware

d?id=CVE-2023-54233 Référence CVE CVE-2023-54234 https://www.cve.org/CVERecord?id=CVE-2023-54234 Référence CVE CVE-2023-54237 https://www.cve.org/CVERecord?id=CVE-2023-54237 Référence CVE CVE-2023-54242 https://www.cve.org/CVERecord?id=CVE-2023-54242 Référence CVE CVE-2023-54247 https://www.cve.org/CVERecord?id=CVE-2023-54247 Référence CVE CVE-2023-54253 https://www.cve.org/CVERecord?id=CVE-2023-54253 Référence CVE CVE-2023-54259 https://www.cve.org/CVERecord?id=CVE-2023-54259 Référence CVE CVE-2023-54261 https://www.cve.org/CVERecord?id=CVE-2023-54261 Référence CVE CVE-2023-54263 https://www.cve.org/CVERecord?id=CVE-2023-54263 Référence CVE CVE-2023-54271 https://www.cve.org/CVERecord?id=CVE-2023-54271 Référence CVE CVE-2023-54280 https://www.cve.org/CVERecord?id=CVE-2023-54280 Référence CVE CVE-2023-54285 https://www.cve.org/CVERecord?id=CVE-2023-54285 Référence CVE CVE-2023-54320 https://www.cve.org/CVERecord?id=CVE-2023-54320 Référence CVE CVE-2023-54323 https://www.cve.org/CVERecord?id=CVE-2023-54323 Référence CVE CVE-2023-54324 https://www.cve.org/CVERecord?id=CVE-2023-54324 Référence CVE CVE-2023-5678 https://www.cve.org/CVERecord?id=CVE-2023-5678 Référence CVE CVE-2023-6129 https://www.cve.org/CVERecord?id=CVE-2023-6129 Référence CVE CVE-2023-6237 https://www.cve.org/CVERecord?id=CVE-2

Official advisory ↗
CERT-FR · French · CERTFR-2026-AVI-0316Multiples vulnérabilités dans les produits VMware

d?id=CVE-2023-54233 Référence CVE CVE-2023-54234 https://www.cve.org/CVERecord?id=CVE-2023-54234 Référence CVE CVE-2023-54237 https://www.cve.org/CVERecord?id=CVE-2023-54237 Référence CVE CVE-2023-54242 https://www.cve.org/CVERecord?id=CVE-2023-54242 Référence CVE CVE-2023-54247 https://www.cve.org/CVERecord?id=CVE-2023-54247 Référence CVE CVE-2023-54253 https://www.cve.org/CVERecord?id=CVE-2023-54253 Référence CVE CVE-2023-54259 https://www.cve.org/CVERecord?id=CVE-2023-54259 Référence CVE CVE-2023-54261 https://www.cve.org/CVERecord?id=CVE-2023-54261 Référence CVE CVE-2023-54263 https://www.cve.org/CVERecord?id=CVE-2023-54263 Référence CVE CVE-2023-54271 https://www.cve.org/CVERecord?id=CVE-2023-54271 Référence CVE CVE-2023-54280 https://www.cve.org/CVERecord?id=CVE-2023-54280 Référence CVE CVE-2023-54285 https://www.cve.org/CVERecord?id=CVE-2023-54285 Référence CVE CVE-2023-54320 https://www.cve.org/CVERecord?id=CVE-2023-54320 Référence CVE CVE-2023-54323 https://www.cve.org/CVERecord?id=CVE-2023-54323 Référence CVE CVE-2023-54324 https://www.cve.org/CVERecord?id=CVE-2023-54324 Référence CVE CVE-2023-5678 https://www.cve.org/CVERecord?id=CVE-2023-5678 Référence CVE CVE-2023-6129 https://www.cve.org/CVERecord?id=CVE-2023-6129 Référence CVE CVE-2023-6237 https://www.cve.org/CVERecord?id=CVE-2

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

d?id=CVE-2023-54253 Référence CVE CVE-2023-54254 https://www.cve.org/CVERecord?id=CVE-2023-54254 Référence CVE CVE-2023-54255 https://www.cve.org/CVERecord?id=CVE-2023-54255 Référence CVE CVE-2023-54258 https://www.cve.org/CVERecord?id=CVE-2023-54258 Référence CVE CVE-2023-54261 https://www.cve.org/CVERecord?id=CVE-2023-54261 Référence CVE CVE-2023-54263 https://www.cve.org/CVERecord?id=CVE-2023-54263 Référence CVE CVE-2023-54264 https://www.cve.org/CVERecord?id=CVE-2023-54264 Référence CVE CVE-2023-54266 https://www.cve.org/CVERecord?id=CVE-2023-54266 Référence CVE CVE-2023-54267 https://www.cve.org/CVERecord?id=CVE-2023-54267 Référence CVE CVE-2023-54271 https://www.cve.org/CVERecord?id=CVE-2023-54271 Référence CVE CVE-2023-54276 https://www.cve.org/CVERecord?id=CVE-2023-54276 Référence CVE CVE-2023-54278 https://www.cve.org/CVERecord?id=CVE-2023-54278 Référence CVE CVE-2023-54281 https://www.cve.org/CVERecord?id=CVE-2023-54281 Référence CVE CVE-2023-54282 https://www.cve.org/CVERecord?id=CVE-2023-54282 Référence CVE CVE-2023-54283 https://www.cve.org/CVERecord?id=CVE-2023-54283 Référence CVE CVE-2023-54285 https://www.cve.org/CVERecord?id=CVE-2023-54285 Référence CVE CVE-2023-54289 https://www.cve.org/CVERecord?id=CVE-2023-54289 Référence CVE CVE-2023-54291 https://www.cve.org/CVERecord?id=

Official advisory ↗
CERT-FR · French · CERTFR-2026-AVI-0225Multiples vulnérabilités dans le noyau Linux de SUSE

d?id=CVE-2023-54258 Référence CVE CVE-2023-54260 https://www.cve.org/CVERecord?id=CVE-2023-54260 Référence CVE CVE-2023-54261 https://www.cve.org/CVERecord?id=CVE-2023-54261 Référence CVE CVE-2023-54263 https://www.cve.org/CVERecord?id=CVE-2023-54263 Référence CVE CVE-2023-54264 https://www.cve.org/CVERecord?id=CVE-2023-54264 Référence CVE CVE-2023-54266 https://www.cve.org/CVERecord?id=CVE-2023-54266 Référence CVE CVE-2023-54267 https://www.cve.org/CVERecord?id=CVE-2023-54267 Référence CVE CVE-2023-54269 https://www.cve.org/CVERecord?id=CVE-2023-54269 Référence CVE CVE-2023-54270 https://www.cve.org/CVERecord?id=CVE-2023-54270 Référence CVE CVE-2023-54271 https://www.cve.org/CVERecord?id=CVE-2023-54271 Référence CVE CVE-2023-54274 https://www.cve.org/CVERecord?id=CVE-2023-54274 Référence CVE CVE-2023-54275 https://www.cve.org/CVERecord?id=CVE-2023-54275 Référence CVE CVE-2023-54276 https://www.cve.org/CVERecord?id=CVE-2023-54276 Référence CVE CVE-2023-54277 https://www.cve.org/CVERecord?id=CVE-2023-54277 Référence CVE CVE-2023-54278 https://www.cve.org/CVERecord?id=CVE-2023-54278 Référence CVE CVE-2023-54280 https://www.cve.org/CVERecord?id=CVE-2023-54280 Référence CVE CVE-2023-54281 https://www.cve.org/CVERecord?id=CVE-2023-54281 Référence CVE CVE-2023-54282 https://www.cve.org/CVERecord?id=

Official advisory ↗
CERT-FR · French · CERTFR-2026-AVI-0170Multiples vulnérabilités dans le noyau Linux de SUSE

d?id=CVE-2023-54244 Référence CVE CVE-2023-54245 https://www.cve.org/CVERecord?id=CVE-2023-54245 Référence CVE CVE-2023-54252 https://www.cve.org/CVERecord?id=CVE-2023-54252 Référence CVE CVE-2023-54260 https://www.cve.org/CVERecord?id=CVE-2023-54260 Référence CVE CVE-2023-54264 https://www.cve.org/CVERecord?id=CVE-2023-54264 Référence CVE CVE-2023-54265 https://www.cve.org/CVERecord?id=CVE-2023-54265 Référence CVE CVE-2023-54266 https://www.cve.org/CVERecord?id=CVE-2023-54266 Référence CVE CVE-2023-54269 https://www.cve.org/CVERecord?id=CVE-2023-54269 Référence CVE CVE-2023-54270 https://www.cve.org/CVERecord?id=CVE-2023-54270 Référence CVE CVE-2023-54271 https://www.cve.org/CVERecord?id=CVE-2023-54271 Référence CVE CVE-2023-54274 https://www.cve.org/CVERecord?id=CVE-2023-54274 Référence CVE CVE-2023-54275 https://www.cve.org/CVERecord?id=CVE-2023-54275 Référence CVE CVE-2023-54277 https://www.cve.org/CVERecord?id=CVE-2023-54277 Référence CVE CVE-2023-54280 https://www.cve.org/CVERecord?id=CVE-2023-54280 Référence CVE CVE-2023-54282 https://www.cve.org/CVERecord?id=CVE-2023-54282 Référence CVE CVE-2023-54284 https://www.cve.org/CVERecord?id=CVE-2023-54284 Référence CVE CVE-2023-54286 https://www.cve.org/CVERecord?id=CVE-2023-54286 Référence CVE CVE-2023-54287 https://www.cve.org/CVERecord?id=

Official advisory ↗
CERT-FR · French · CERTFR-2026-AVI-0108Multiples vulnérabilités dans le noyau Linux de SUSE

d?id=CVE-2023-54260 Référence CVE CVE-2023-54261 https://www.cve.org/CVERecord?id=CVE-2023-54261 Référence CVE CVE-2023-54262 https://www.cve.org/CVERecord?id=CVE-2023-54262 Référence CVE CVE-2023-54263 https://www.cve.org/CVERecord?id=CVE-2023-54263 Référence CVE CVE-2023-54264 https://www.cve.org/CVERecord?id=CVE-2023-54264 Référence CVE CVE-2023-54266 https://www.cve.org/CVERecord?id=CVE-2023-54266 Référence CVE CVE-2023-54267 https://www.cve.org/CVERecord?id=CVE-2023-54267 Référence CVE CVE-2023-54269 https://www.cve.org/CVERecord?id=CVE-2023-54269 Référence CVE CVE-2023-54270 https://www.cve.org/CVERecord?id=CVE-2023-54270 Référence CVE CVE-2023-54271 https://www.cve.org/CVERecord?id=CVE-2023-54271 Référence CVE CVE-2023-54274 https://www.cve.org/CVERecord?id=CVE-2023-54274 Référence CVE CVE-2023-54275 https://www.cve.org/CVERecord?id=CVE-2023-54275 Référence CVE CVE-2023-54276 https://www.cve.org/CVERecord?id=CVE-2023-54276 Référence CVE CVE-2023-54277 https://www.cve.org/CVERecord?id=CVE-2023-54277 Référence CVE CVE-2023-54278 https://www.cve.org/CVERecord?id=CVE-2023-54278 Référence CVE CVE-2023-54280 https://www.cve.org/CVERecord?id=CVE-2023-54280 Référence CVE CVE-2023-54281 https://www.cve.org/CVERecord?id=CVE-2023-54281 Référence CVE CVE-2023-54282 https://www.cve.org/CVERecord?id=

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
Fixed
Linux: < 5.4, 5.15.210 ≤ 5.15.*, 6.1.176 ≤ 6.1.*, 6.4.16 ≤ 6.4.*, 6.5.3 ≤ 6.5.*, 6.6 ≤ *
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 30 Dec 2025 · Last source change 19 Jun 2026, 11:57 UTC · CWE not yet assigned

CVE recordCVE.org · 5.2
CVSS sourceUnavailable
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-2023-60370
Product sourceVendor CSAF · SUSE Product Security Team
Remediation sourceVendor CSAF · SUSE Product Security Team
CWE sourceUnavailable
NVD statusNVD not scheduled

Missing structured fields: CVSS base score, CWE classification. Missing data is not evidence of low risk; review the primary advisory.

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
CVE published
Fixed release or patch reference recorded
ENISA EUVD · EUVD-2023-60370↗Vendor CSAF · SUSE Product Security Team↗CVE authority or vendor reference↗Official CVE record (CNA and ADP data)↗NVD record↗
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-2023-54271 · cve.blacktree.nl