Linux Kernel up to 6.12.55/6.17.5 hw_init null pointer dereference

Summaryinfo

A vulnerability has been found in Linux Kernel up to 6.12.55/6.17.5 and classified as critical. The impacted element is the function hw_init. Performing a manipulation results in null pointer dereference. This vulnerability is reported as CVE-2025-40354. No exploit exists. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as critical has been found in Linux Kernel up to 6.12.55/6.17.5. This affects the function hw_init. 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: drm/amd/display: increase max link count and fix link->enc NULL pointer access [why] 1.) dc->links[MAX_LINKS] array size smaller than actual requested. max_connector + max_dpia + 4 virtual = 14. increase from 12 to 14. 2.) hw_init() access null LINK_ENC for dpia non display_endpoint. (cherry picked from commit d7f5a61e1b04ed87b008c8d327649d184dc5bb45)

The advisory is shared at git.kernel.org. This vulnerability is uniquely identified as CVE-2025-40354 since 04/16/2025. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 298897 (Ubuntu 25.10 : Linux kernel vulnerabilities (USN-8029-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.12.56 or 6.17.6 eliminates this vulnerability. Applying the patch f28092be4e12b7df9e4f415d25bf0d767bc2d9ed/a3fc0d36cfb927f8986b83bf5fba47dbedad3c63/bec947cbe9a65783adb475a5fb47980d7b4f4796 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 (298897), EUVD (EUVD-2025-203633) and CERT Bund (WID-SEC-2025-2868). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• SUSE openSUSE
• RESF Rocky Linux
• 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
• 6.17.0
• 6.17.1
• 6.17.2
• 6.17.3
• 6.17.4
• 6.17.5

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Exploitinginfo

Threat Intelligenceinfo

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Sourcesinfo

Entryinfo

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