Linux Kernel up to 6.12.71/6.18.10/6.19.0 xfs xchk_btree_check_block_owner null pointer dereference

CVSS Meta Temp Score
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CTI Interest Score
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6.6$0-$5k0.00

Summaryinfo

A vulnerability marked as critical has been reported in Linux Kernel up to 6.12.71/6.18.10/6.19.0. The affected element is the function xchk_btree_check_block_owner of the component xfs. Performing a manipulation results in null pointer dereference. This vulnerability is cataloged as CVE-2026-23223. There is no exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in Linux Kernel up to 6.12.71/6.18.10/6.19.0. This affects the function xchk_btree_check_block_owner of the component xfs. The manipulation with an unknown input leads to a null pointer dereference vulnerability. CWE is classifying the issue as CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. This is going to have an impact on availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: xfs: fix UAF in xchk_btree_check_block_owner We cannot dereference bs->cur when trying to determine if bs->cur aliases bs->sc->sa.{bno,rmap}_cur after the latter has been freed. Fix this by sampling before type before any freeing could happen. The correct temporal ordering was broken when we removed xfs_btnum_t.

It is possible to read the advisory at git.kernel.org. This vulnerability is uniquely identified as CVE-2026-23223 since 01/13/2026. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 299436 (Linux Distros Unpatched Vulnerability : CVE-2026-23223), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.12.72, 6.18.11 or 6.19.1 eliminates this vulnerability. Applying the patch 1d411278dda293a507cb794db7d9ed3511c685c6/ed82e7949f5cac3058f4100f3cd670531d41a266/ba5264610423d9653aa36920520902d83841bcfd 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 (299436) and CERT Bund (WID-SEC-2026-0462). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

  • Open Source Linux Kernel

Productinfo

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Version

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.7
VulDB Meta Temp Score: 6.6

VulDB Base Score: 5.7
VulDB Temp Score: 5.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: Null pointer dereference
CWE: CWE-476 / CWE-404
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: 299436
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-23223

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.12.72/6.18.11/6.19.1
Patch: 1d411278dda293a507cb794db7d9ed3511c685c6/ed82e7949f5cac3058f4100f3cd670531d41a266/ba5264610423d9653aa36920520902d83841bcfd

Timelineinfo

01/13/2026 CVE reserved
02/18/2026 +36 days Advisory disclosed
02/18/2026 +0 days VulDB entry created
03/19/2026 +29 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-23223 (🔒)
GCVE (CVE): GCVE-0-2026-23223
GCVE (VulDB): GCVE-100-346539
CERT Bund: WID-SEC-2026-0462 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 02/18/2026 17:00
Updated: 03/19/2026 09:01
Changes: 02/18/2026 17:00 (59), 02/20/2026 02:08 (2), 02/20/2026 03:07 (7), 02/23/2026 06:53 (1), 03/19/2026 09:01 (11)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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