Skip to content
Noroxi
NVD / CVE Program· CNA Linux

CVE-2025-40125: blk-mq: check kobject state_in_sysfs before deleting in blk_mq_unregister_hctx

Noroxi assessment

Priority: Monitor (action score 0/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.22% (FIRST EPSS).
  • Fixed version: Linux Linux 06c4826b1d900611096e4621e93133db57e13911, 4b97e99b87a773d52699521d40864f3ec888e9a6, 4c7ef92f6d4d08a27d676e4c348f4e2922cab3ed.

Low priority for now. Upgrade to Linux Linux 06c4826b1d900611096e4621e93133db57e13911, 4b97e99b87a773d52699521d40864f3ec888e9a6, 4c7ef92f6d4d08a27d676e4c348f4e2922cab3ed or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

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.

—No exploit Fix available
Published
Nov 12, 2025
Updated
Oct 19, 2026
EPSS
0.2% · 13th percentile
CWE
—

Report tools

JSON

Action score

0

Monitor

Low priority for now.

CVSS
0 / 40 · —
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.2%

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2025-40125

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

One daily email digest (06:00 UTC); connect a webhook for KEV listings and weaponized exploits instantly.

Your free account also gets you

Running WordPress? Scan your site free with WP Lens

  • Stack alerts: add the products and versions you run, get the new CVEs that affect them
  • Uptime monitoring: 1 site, instant email when it goes down
  • Add your domain: subdomains and takeover risk scanned every week (1 domain)
  • 10 scans an hour on the security tools (3 a day without an account), an API key and MCP
  • All your scans in one panel: findings, what changed in the last scan, a report per domain or per client (PDF, share link)
All free tools

Sign up with email · Have an account? Sign in

Free account, no card. Unfollow any time.

Don't want an account? Get "Exploited this week" by email every MondayDon't want an account? RSS feed for linux records

Running WordPress? Scan your site free with WP Lens

Is your version affected? Check it

Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

We use this product, ask for help

Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

—

Versions reported by the vendor

Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.

  • Linux Linux

    • 4.20affected
    • 477e19dedc9d3e1f4443a1d4ae00572a988120ea and later · before a8c53553f1833cc2d14175d2d72cf37193a01898affected · git
    • 477e19dedc9d3e1f4443a1d4ae00572a988120ea and later · before cc14ea21c4e658814d737ed4dedde6cd626a15adaffected · git
    • 477e19dedc9d3e1f4443a1d4ae00572a988120ea and later · before 4b97e99b87a773d52699521d40864f3ec888e9a6affected · git
    • 477e19dedc9d3e1f4443a1d4ae00572a988120ea and later · before 6e7dadc5763c48eb3b9b91265a21f312599ebb2caffected · git
    • 477e19dedc9d3e1f4443a1d4ae00572a988120ea and later · before 06c4826b1d900611096e4621e93133db57e13911affected · git
    • 477e19dedc9d3e1f4443a1d4ae00572a988120ea and later · before babc634e9fe2803962dba98a07587e835dbc0731affected · git
    • 477e19dedc9d3e1f4443a1d4ae00572a988120ea and later · before d5ddd76ee52bdc16e9f8b1e7791291e785dab032affected · git
    • 477e19dedc9d3e1f4443a1d4ae00572a988120ea and later · before 4c7ef92f6d4d08a27d676e4c348f4e2922cab3edaffected · git
    • before 4.20not affected · semver

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:12linuxbefore 6.1.158-16.1.158-1
Debian:13linuxbefore 6.12.57-16.12.57-1
Debian:14linuxbefore 6.17.6-16.17.6-1

Same product

linux: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-74705udp: fix potential use-after-free in tunnel segmentation
    40Plan
  • CVE-2026-74612veth: fix skb length accounting after XDP frag adjustment
    40Plan
  • CVE-2026-74475vxlan: use neigh_ha_snapshot() in route_shortcircuit()
    40Plan

Published before and after this one in the same product

  • ← EarlierCVE-2025-40123Nov 12, 2025 · bpf: Enforce expected_attach_type for tailcall compatibility
    31Monitor
  • ← EarlierCVE-2025-40124Nov 12, 2025 · sparc: fix accurate exception reporting in copy_{from_to}_user for UltraSPARC III
    31Monitor
  • Later →CVE-2025-40126Nov 12, 2025 · sparc: fix accurate exception reporting in copy_{from_to}_user for UltraSPARC
    0Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
Linux Linux06c4826b1d900611096e4621e93133db57e13911Vendor (CNA)
Linux Linux4b97e99b87a773d52699521d40864f3ec888e9a6Vendor (CNA)
Linux Linux4c7ef92f6d4d08a27d676e4c348f4e2922cab3edVendor (CNA)
Linux Linux6e7dadc5763c48eb3b9b91265a21f312599ebb2cVendor (CNA)
Linux Linuxa8c53553f1833cc2d14175d2d72cf37193a01898Vendor (CNA)
Linux Linuxbabc634e9fe2803962dba98a07587e835dbc0731Vendor (CNA)
Linux Linuxcc14ea21c4e658814d737ed4dedde6cd626a15adVendor (CNA)
Linux Linuxd5ddd76ee52bdc16e9f8b1e7791291e785dab032Vendor (CNA)
debian:linux6.1.158-1 · Debian:12Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

No CVSS vector for this record, so attack conditions can't be derived.

Weakness class (CWE)

—

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (7 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records