Linux Kernel up to 6.12.62/6.17.12/6.18.1 md_wakeup_thread use after free

Summaryinfo

A vulnerability classified as critical has been found in Linux Kernel up to 6.12.62/6.17.12/6.18.1. Affected by this vulnerability is the function md_wakeup_thread. This manipulation causes use after free. The identification of this vulnerability is CVE-2025-68374. There is no exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in Linux Kernel up to 6.12.62/6.17.12/6.18.1. Affected by this vulnerability is the function md_wakeup_thread. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: md: fix rcu protection in md_wakeup_thread We attempted to use RCU to protect the pointer 'thread', but directly passed the value when calling md_wakeup_thread(). This means that the RCU pointer has been acquired before rcu_read_lock(), which renders rcu_read_lock() ineffective and could lead to a use-after-free.

It is possible to read the advisory at git.kernel.org. This vulnerability is known as CVE-2025-68374 since 12/16/2025. The exploitation appears to be easy. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 12/25/2025).

The vulnerability scanner Nessus provides a plugin with the ID 279706 (Linux Distros Unpatched Vulnerability : CVE-2025-68374), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.12.63, 6.17.13, 6.18.2 or 6.19-rc1 eliminates this vulnerability. Applying the patch 21989cb5034c835b212385a2afadf279d8069da0/a4bd1caf591faeae44cb10b6517e7dacb5139bda/f98b191f78124405294481dea85f8a22a3eb0a59/0dc76205549b4c25705e54345f211b9f66e018a0 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 (279706) and CERT Bund (WID-SEC-2025-2920). Be aware that VulDB is the high quality source for vulnerability data.

Affected

• Open Source Linux Kernel

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
• 6.12.54
• 6.12.55
• 6.12.56
• 6.12.57
• 6.12.58
• 6.12.59
• 6.12.60
• 6.12.61
• 6.12.62
• 6.17.0
• 6.17.1
• 6.17.2
• 6.17.3
• 6.17.4
• 6.17.5
• 6.17.6
• 6.17.7
• 6.17.8
• 6.17.9
• 6.17.10
• 6.17.11
• 6.17.12
• 6.18.0
• 6.18.1

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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CVSSv4info

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Exploitinginfo

Threat Intelligenceinfo

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Sourcesinfo

Entryinfo

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

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