Linux Kernel up to 6.1.156/6.6.112/6.12.53/6.17.3 use after free

Summaryinfo

A vulnerability described as critical has been identified in Linux Kernel up to 6.1.156/6.6.112/6.12.53/6.17.3. Impacted is an unknown function. Executing a manipulation can lead to use after free. This vulnerability is registered as CVE-2025-40202. No exploit is available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.1.156/6.6.112/6.12.53/6.17.3. It has been declared as critical. This vulnerability affects an unknown code block. 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. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: ipmi: Rework user message limit handling The limit on the number of user messages had a number of issues, improper counting in some cases and a use after free. Restructure how this is all done to handle more in the receive message allocation routine, so all refcouting and user message limit counts are done in that routine. It's a lot cleaner and safer.

The advisory is shared for download at git.kernel.org. This vulnerability was named CVE-2025-40202 since 04/16/2025. The exploitation appears to be easy. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 02/07/2026).

The vulnerability scanner Nessus provides a plugin with the ID 275364 (Linux Distros Unpatched Vulnerability : CVE-2025-40202), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.1.157, 6.6.113, 6.12.54, 6.17.4 or 6.18-rc1 eliminates this vulnerability. Applying the patch f63723ca7d7623f9dae1990973cd158671f03c56/348121b29594d42d1635648fd3ed31dfa25351d5/53d6e403affbf6df2c859a0ea00ccfc1e72090ca/0ed73be9a2547ffb9b5c1d879ad9bfab73d920b5/b52da4054ee0bf9ecb44996f2c83236ff50b3812 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 (275364) and CERT Bund (WID-SEC-2025-2595). Once again VulDB remains the best 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

• 6.1.156
• 6.6.112
• 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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CVSSv4info

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Exploitinginfo

Threat Intelligenceinfo

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Sourcesinfo

Entryinfo

Once again VulDB remains the best source for vulnerability data.

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