Linux Kernel up to 6.6.108/6.12.49/6.16.9 SMB Client smb2_compound_op out-of-bounds

Summaryinfo

A vulnerability has been found in Linux Kernel up to 6.6.108/6.12.49/6.16.9 and classified as critical. This vulnerability affects the function smb2_compound_op of the component SMB Client. This manipulation causes out-of-bounds. The identification of this vulnerability is CVE-2025-39975. There is no exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 6.6.108/6.12.49/6.16.9 and classified as problematic. Affected by this vulnerability is the function smb2_compound_op of the component SMB Client. The manipulation with an unknown input leads to a out-of-bounds vulnerability. The CWE definition for the vulnerability is CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: smb: client: fix wrong index reference in smb2_compound_op() In smb2_compound_op(), the loop that processes each command's response uses wrong indices when accessing response bufferes. This incorrect indexing leads to improper handling of command results. Also, if incorrectly computed index is greather than or equal to MAX_COMPOUND, it can cause out-of-bounds accesses.

It is possible to read the advisory at git.kernel.org. This vulnerability is known as CVE-2025-39975 since 04/16/2025. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 271546 (Linux Distros Unpatched Vulnerability : CVE-2025-39975), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.6.109, 6.12.50 or 6.16.10 eliminates this vulnerability. Applying the patch ba7bcfd52c66dd1c2dfa5142aca7e4a70b62dfa5/bfb1e2aad1fecef8320fd71332acde0d53a8d699/093615fc76063ea08d454ba86677ce64c736e806/fbe2dc6a9c7318f7263f5e4d50f6272b931c5756 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 (271546) and CERT Bund (WID-SEC-2025-2298). 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
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• SUSE openSUSE
• RESF Rocky Linux
• Open Source Linux Kernel
• IBM QRadar SIEM
• Dell NetWorker

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.6.108
• 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
• 6.16.0
• 6.16.1
• 6.16.2
• 6.16.3
• 6.16.4
• 6.16.5
• 6.16.6
• 6.16.7
• 6.16.8
• 6.16.9

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Exploitinginfo

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Entryinfo

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