Linux Kernel up to 6.6.121/6.12.67/6.18.7/6.19-rc6 scsi_dec_host_busy race condition

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4.6$0-$5k0.00

Summaryinfo

A vulnerability identified as critical has been detected in Linux Kernel up to 6.6.121/6.12.67/6.18.7/6.19-rc6. This impacts the function scsi_dec_host_busy. This manipulation causes race condition. This vulnerability appears as CVE-2026-23110. There is no available exploit. You should upgrade the affected component.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 6.6.121/6.12.67/6.18.7/6.19-rc6 and classified as critical. Affected by this vulnerability is the function scsi_dec_host_busy. The manipulation with an unknown input leads to a race condition vulnerability. The CWE definition for the vulnerability is CWE-362. The product contains a code sequence that can run concurrently with other code, and the code sequence requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence that is operating concurrently. The impact remains unknown. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: scsi: core: Wake up the error handler when final completions race against each other The fragile ordering between marking commands completed or failed so that the error handler only wakes when the last running command completes or times out has race conditions. These race conditions can cause the SCSI layer to fail to wake the error handler, leaving I/O through the SCSI host stuck as the error state cannot advance. First, there is an memory ordering issue within scsi_dec_host_busy(). The write which clears SCMD_STATE_INFLIGHT may be reordered with reads counting in scsi_host_busy(). While the local CPU will see its own write, reordering can allow other CPUs in scsi_dec_host_busy() or scsi_eh_inc_host_failed() to see a raised busy count, causing no CPU to see a host busy equal to the host_failed count. This race condition can be prevented with a memory barrier on the error path to force the write to be visible before counting host busy commands. Second, there is a general ordering issue with scsi_eh_inc_host_failed(). By counting busy commands before incrementing host_failed, it can race with a final command in scsi_dec_host_busy(), such that scsi_dec_host_busy() does not see host_failed incremented but scsi_eh_inc_host_failed() counts busy commands before SCMD_STATE_INFLIGHT is cleared by scsi_dec_host_busy(), resulting in neither waking the error handler task. This needs the call to scsi_host_busy() to be moved after host_failed is incremented to close the race condition.

The advisory is shared at git.kernel.org. This vulnerability is known as CVE-2026-23110 since 01/13/2026. The exploitation appears to be difficult. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 297876 (Linux Distros Unpatched Vulnerability : CVE-2026-23110), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.6.122, 6.12.68, 6.18.8 or 6.19-rc7 eliminates this vulnerability. Applying the patch 9fdc6f28d5e81350ab1d2cac8389062bd09e61e1/64ae21b9c4f0c7e60cf47a53fa7ab68852079ef0/219f009ebfd1ef3970888ee9eef4c8a06357f862/fe2f8ad6f0999db3b318359a01ee0108c703a8c3 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 (297876) and CERT Bund (WID-SEC-2026-0324). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

  • Debian Linux
  • Google Cloud Platform
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • IBM QRadar SIEM
  • SUSE openSUSE
  • RESF Rocky Linux
  • Open Source Linux Kernel

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: 4.6

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

NVD Base Score: 4.7
NVD Vector: 🔒

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Race condition
CWE: CWE-362
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 297876
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-23110

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.6.122/6.12.68/6.18.8/6.19-rc7
Patch: 9fdc6f28d5e81350ab1d2cac8389062bd09e61e1/64ae21b9c4f0c7e60cf47a53fa7ab68852079ef0/219f009ebfd1ef3970888ee9eef4c8a06357f862/fe2f8ad6f0999db3b318359a01ee0108c703a8c3

Timelineinfo

01/13/2026 CVE reserved
02/04/2026 +22 days Advisory disclosed
02/04/2026 +0 days VulDB entry created
05/03/2026 +88 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-23110 (🔒)
GCVE (CVE): GCVE-0-2026-23110
GCVE (VulDB): GCVE-100-344353
CERT Bund: WID-SEC-2026-0324 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 02/04/2026 18:30
Updated: 05/03/2026 20:14
Changes: 02/04/2026 18:30 (58), 02/08/2026 07:39 (2), 03/19/2026 00:23 (11), 05/03/2026 20:14 (7)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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