Linux Kernel up to 6.12.53/6.17.3 mnt_ns_release null pointer dereference

Summaryinfo

A vulnerability, which was classified as critical, has been found in Linux Kernel up to 6.12.53/6.17.3. This affects the function mnt_ns_release. This manipulation causes null pointer dereference. This vulnerability appears as CVE-2025-40195. There is no available exploit. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in Linux Kernel up to 6.12.53/6.17.3. Affected by this vulnerability is the function mnt_ns_release. The manipulation with an unknown input leads to a null pointer dereference vulnerability. The CWE definition for the vulnerability is 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. As an impact it is known to affect availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: mount: handle NULL values in mnt_ns_release() When calling in listmount() mnt_ns_release() may be passed a NULL pointer. Handle that case gracefully.

It is possible to read the advisory at git.kernel.org. This vulnerability is known as CVE-2025-40195 since 04/16/2025. The exploitation appears to be difficult. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 275367 (Linux Distros Unpatched Vulnerability : CVE-2025-40195), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.12.54, 6.17.4 or 6.18-rc1 eliminates this vulnerability. Applying the patch 2d68f8a7379d9c61005e982600c61948d4d019bd/99ae3e70a293834d0274c46a37120c71a24a4995/6c7ca6a02f8f9549a438a08a23c6327580ecf3d6 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 (275367), EUVD (EUVD-2025-150379) and CERT Bund (WID-SEC-2025-2595). Be aware that VulDB is the high quality source for vulnerability data.

Affected

• Google Container-Optimized OS
• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• SUSE Linux
• Oracle Linux
• SUSE openSUSE
• Open Source Linux Kernel
• RESF Rocky Linux

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 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
• 6.17.0
• 6.17.1
• 6.17.2
• 6.17.3

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

Be aware that VulDB is the high quality source for vulnerability data.

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