Linux Kernel up to 6.17.2 fs/kernfs/dir.c __blk_mq_update_nr_hw_queues return value

CVSS Meta Temp Score
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CTI Interest Score
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4.4$0-$5k0.00

Summaryinfo

A vulnerability classified as critical was found in Linux Kernel up to 6.17.2. This affects the function __blk_mq_update_nr_hw_queues of the file fs/kernfs/dir.c. The manipulation results in return value. This vulnerability is identified as CVE-2025-40125. There is not any exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability classified as critical has been found in Linux Kernel up to 6.17.2. Affected is the function __blk_mq_update_nr_hw_queues of the file fs/kernfs/dir.c. The manipulation with an unknown input leads to a return value vulnerability. CWE is classifying the issue as CWE-252. The product does not check the return value from a method or function, which can prevent it from detecting unexpected states and conditions. The impact remains unknown. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: blk-mq: check kobject state_in_sysfs before deleting in blk_mq_unregister_hctx In __blk_mq_update_nr_hw_queues() the return value of blk_mq_sysfs_register_hctxs() is not checked. If sysfs creation for hctx fails, later changing the number of hw_queues or removing disk will trigger the following warning: kernfs: can not remove 'nr_tags', no directory WARNING: CPU: 2 PID: 637 at fs/kernfs/dir.c:1707 kernfs_remove_by_name_ns+0x13f/0x160 Call Trace: remove_files.isra.1+0x38/0xb0 sysfs_remove_group+0x4d/0x100 sysfs_remove_groups+0x31/0x60 __kobject_del+0x23/0xf0 kobject_del+0x17/0x40 blk_mq_unregister_hctx+0x5d/0x80 blk_mq_sysfs_unregister_hctxs+0x94/0xd0 blk_mq_update_nr_hw_queues+0x124/0x760 nullb_update_nr_hw_queues+0x71/0xf0 [null_blk] nullb_device_submit_queues_store+0x92/0x120 [null_blk] kobjct_del() was called unconditionally even if sysfs creation failed. Fix it by checkig the kobject creation statusbefore deleting it.

The advisory is shared for download at git.kernel.org. This vulnerability is traded as CVE-2025-40125 since 04/16/2025. The exploitability is told to be difficult. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 02/08/2026).

The vulnerability scanner Nessus provides a plugin with the ID 276782 (Debian dla-4379 : linux-config-6.1 - security update), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.4.301, 5.10.246, 5.15.195, 6.1.156, 6.6.112, 6.12.53, 6.17.3 or 6.18-rc1 eliminates this vulnerability. Applying the patch a8c53553f1833cc2d14175d2d72cf37193a01898/cc14ea21c4e658814d737ed4dedde6cd626a15ad/4b97e99b87a773d52699521d40864f3ec888e9a6/6e7dadc5763c48eb3b9b91265a21f312599ebb2c/06c4826b1d900611096e4621e93133db57e13911/babc634e9fe2803962dba98a07587e835dbc0731/d5ddd76ee52bdc16e9f8b1e7791291e785dab032/4c7ef92f6d4d08a27d676e4c348f4e2922cab3ed is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (276782) and CERT Bund (WID-SEC-2025-2579). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

  • Google Container-Optimized OS
  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • SUSE openSUSE
  • Open Source Linux Kernel
  • RESF Rocky Linux

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.6
VulDB Meta Temp Score: 4.4

VulDB Base Score: 4.6
VulDB Temp Score: 4.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Return value
CWE: CWE-252 / CWE-253
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 276782
Nessus Name: Debian dla-4379 : linux-config-6.1 - security update

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 5.4.301/5.10.246/5.15.195/6.1.156/6.6.112/6.12.53/6.17.3/6.18-rc1
Patch: a8c53553f1833cc2d14175d2d72cf37193a01898/cc14ea21c4e658814d737ed4dedde6cd626a15ad/4b97e99b87a773d52699521d40864f3ec888e9a6/6e7dadc5763c48eb3b9b91265a21f312599ebb2c/06c4826b1d900611096e4621e93133db57e13911/babc634e9fe2803962dba98a07587e835dbc0731/d5ddd76ee52bdc16e9f8b1e7791291e785dab032/4c7ef92f6d4d08a27d676e4c348f4e2922cab3ed

Timelineinfo

04/16/2025 CVE reserved
11/12/2025 +210 days Advisory disclosed
11/12/2025 +0 days VulDB entry created
02/08/2026 +88 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2025-40125 (🔒)
GCVE (CVE): GCVE-0-2025-40125
GCVE (VulDB): GCVE-100-332136
CERT Bund: WID-SEC-2025-2579 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 11/12/2025 13:30
Updated: 02/08/2026 01:03
Changes: 11/12/2025 13:30 (59), 11/28/2025 21:48 (2), 12/18/2025 01:31 (7), 12/30/2025 13:54 (1), 02/08/2026 01:03 (1)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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