CVE-2025-68756

Service hang via recursive tag-list locking

Published Jan 5, 2026 · Updated Jan 5, 2026

Deadlock in the Linux Kernel block layer from 6.2 allows attackers to hang NVMe I/O during concurrent timeout handling and queue removal. blk_mq_quiesce_tagset() takes set->tag_list_lock while a queue-removal path already holds that mutex and waits for queue usage to drain. Reachability requires an NVMe command timeout to overlap tag-set membership changes, after which both kernel threads wait indefinitely and affected storage work stalls.

CVSS severityUnavailable
Unscored
EPSS probability0.18%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Deadlock in the Linux Kernel block layer from 6.2 allows attackers to hang NVMe I/O during concurrent timeout handling and queue removal. blk_mq_quiesce_tagset() takes set->tag_list_lock while a queue-removal path already holds that mutex and waits for queue usage to drain. Reachability requires an NVMe command timeout to overlap tag-set membership changes, after which both kernel threads wait indefinitely and affected storage work stalls.

The record

CVE
CVE-2025-68756
Published
Jan 5, 2026
Updated
Jan 5, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
Unavailable
Attack vector
local
Privileges
Unavailable

Timeline

How it unfolded

  1. Jan 5, 2026CVE publishedPublication date reported by the CVE source.
  2. Jan 5, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=6.2
  2. Affected versionversion=98d81f0df70ce6fc48517d938026e3c684b9051a <3baeec23a82e7ee9691f434c6ab0ab1387326108
  3. Affected versionversion=98d81f0df70ce6fc48517d938026e3c684b9051a <59e25ef2b413c72da6686d431e7759302cfccafa
  4. Affected versionversion=98d81f0df70ce6fc48517d938026e3c684b9051a <6e8d363786765a81e35083e0909e076796468edf
  5. Affected versionversion=98d81f0df70ce6fc48517d938026e3c684b9051a <ef0cd7b694928573f6569e61c14f5f059253162e

What conditions does exploitation require?

Attack vectorlocal
Required privilegesUnavailable in this record.

What is affected?

The Linux Kernel Organization · Linux Kernelversion=6.2; version=98d81f0df70ce6fc48517d938026e3c684b9051a <3baeec23a82e7ee9691f434c6ab0ab1387326108; version=98d81f0df70ce6fc48517d938026e3c684b9051a <59e25ef2b413c72da6686d431e7759302cfccafa; version=98d81f0df70ce6fc48517d938026e3c684b9051a <6e8d363786765a81e35083e0909e076796468edf; version=98d81f0df70ce6fc48517d938026e3c684b9051a <ef0cd7b694928573f6569e61c14f5f059253162e

Published CVSS scores

No CVSS assessment is available in this record.

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

No sourced classifications are available.

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo