Linux Kernel up to 6.1.153/6.6.107/6.12.48/6.16.8 SMB Client smbd_negotiate memory leak

Summaryinfo

A vulnerability classified as critical has been found in Linux Kernel up to 6.1.153/6.6.107/6.12.48/6.16.8. The affected element is the function smbd_negotiate of the component SMB Client. This manipulation causes memory leak. This vulnerability is registered as CVE-2025-39929. No exploit is available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in Linux Kernel up to 6.1.153/6.6.107/6.12.48/6.16.8. Affected by this vulnerability is the function smbd_negotiate of the component SMB Client. The manipulation with an unknown input leads to a memory leak vulnerability. The CWE definition for the vulnerability is CWE-401. The product does not sufficiently track and release allocated memory after it has been used, which slowly consumes remaining memory. As an impact it is known to affect availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: smb: client: fix smbdirect_recv_io leak in smbd_negotiate() error path During tests of another unrelated patch I was able to trigger this error: Objects remaining on __kmem_cache_shutdown()

The advisory is shared at git.kernel.org. This vulnerability is known as CVE-2025-39929 since 04/16/2025. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 269452 (Linux Distros Unpatched Vulnerability : CVE-2025-39929), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.1.154, 6.6.108, 6.12.49 or 6.16.9 eliminates this vulnerability. Applying the patch 3d7c075c878ac844e33c43e506c2fa27ac7e9689/e7b7a93879558e77d950f1ff9a6f3daa385b33df/922338efaad63cfe30d459dfc59f9d69ff93ded4/0991418bf98f191d0c320bd25245fcffa1998c7e/daac51c7032036a0ca5f1aa419ad1b0471d1c6e0 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 (269452) and CERT Bund (WID-SEC-2025-2194). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

• Google Container-Optimized OS
• Debian Linux
• Google Cloud Platform
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• SUSE openSUSE
• Open Source Linux Kernel
• RESF Rocky Linux
• NetApp ActiveIQ Unified Manager
• IBM QRadar SIEM
• Dell NetWorker

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.1.153
• 6.6.107
• 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
• 6.16.0
• 6.16.1
• 6.16.2
• 6.16.3
• 6.16.4
• 6.16.5
• 6.16.6
• 6.16.7
• 6.16.8

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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CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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