Linux Kernel up to 6.6.123/6.12.69/6.18.9 smb smb2_open reference count

Summaryinfo

A vulnerability, which was classified as critical, was found in Linux Kernel up to 6.6.123/6.12.69/6.18.9. This affects the function smb2_open of the component smb. The manipulation results in reference count. This vulnerability was named CVE-2025-71223. There is no available exploit. You should upgrade the affected component.

Detailsinfo

A vulnerability classified as critical has been found in Linux Kernel up to 6.6.123/6.12.69/6.18.9. Affected is the function smb2_open of the component smb. The manipulation with an unknown input leads to a reference count vulnerability. CWE is classifying the issue as CWE-911. The product uses a reference count to manage a resource, but it does not update or incorrectly updates the reference count. This is going to have an impact on availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: smb/server: fix refcount leak in smb2_open() When ksmbd_vfs_getattr() fails, the reference count of ksmbd_file must be released.

The advisory is shared for download at git.kernel.org. This vulnerability is traded as CVE-2025-71223 since 02/14/2026. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 299095 (Linux Distros Unpatched Vulnerability : CVE-2025-71223), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.6.124, 6.12.70 or 6.18.10 eliminates this vulnerability. Applying the patch 2456fde2b137703328f1695f60c68fe488d17e36/39ca11ff158c98fb092176f06047628c54bcf7a1/4665e52bde3b1f8f442895ce7d88fa62a43e48c4/f416c556997aa56ec4384c6b6efd6a0e6ac70aa7 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 (299095) and CERT Bund (WID-SEC-2026-0421). Once again VulDB remains the best source for vulnerability data.

Affected

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

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.6.123
• 6.12.0
• 6.12.1
• 6.12.2
• 6.12.3
• 6.12.4
• 6.12.5
• 6.12.6
• 6.12.7
• 6.12.8
• 6.12.9
• 6.12.10
• 6.12.11
• 6.12.12
• 6.12.13
• 6.12.14
• 6.12.15
• 6.12.16
• 6.12.17
• 6.12.18
• 6.12.19
• 6.12.20
• 6.12.21
• 6.12.22
• 6.12.23
• 6.12.24
• 6.12.25
• 6.12.26
• 6.12.27
• 6.12.28
• 6.12.29
• 6.12.30
• 6.12.31
• 6.12.32
• 6.12.33
• 6.12.34
• 6.12.35
• 6.12.36
• 6.12.37
• 6.12.38
• 6.12.39
• 6.12.40
• 6.12.41
• 6.12.42
• 6.12.43
• 6.12.44
• 6.12.45
• 6.12.46
• 6.12.47
• 6.12.48
• 6.12.49
• 6.12.50
• 6.12.51
• 6.12.52
• 6.12.53
• 6.12.54
• 6.12.55
• 6.12.56
• 6.12.57
• 6.12.58
• 6.12.59
• 6.12.60
• 6.12.61
• 6.12.62
• 6.12.63
• 6.12.64
• 6.12.65
• 6.12.66
• 6.12.67
• 6.12.68
• 6.12.69
• 6.18.0
• 6.18.1
• 6.18.2
• 6.18.3
• 6.18.4
• 6.18.5
• 6.18.6
• 6.18.7
• 6.18.8
• 6.18.9

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

Once again VulDB remains the best source for vulnerability data.

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