Linux Kernel up to 6.12.74/6.18.15/6.19.5 dlm dlm_dump_rsb_name len buffer overflow

Summaryinfo

A vulnerability identified as critical has been detected in Linux Kernel up to 6.12.74/6.18.15/6.19.5. The affected element is the function dlm_dump_rsb_name of the component dlm. The manipulation of the argument len leads to buffer overflow. This vulnerability is listed as CVE-2026-43125. There is no available exploit. You should upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Linux Kernel up to 6.12.74/6.18.15/6.19.5. This issue affects the function dlm_dump_rsb_name of the component dlm. The manipulation of the argument len with an unknown input leads to a buffer overflow vulnerability. Using CWE to declare the problem leads to CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: dlm: validate length in dlm_search_rsb_tree The len parameter in dlm_dump_rsb_name() is not validated and comes from network messages. When it exceeds DLM_RESNAME_MAXLEN, it can cause out-of-bounds write in dlm_search_rsb_tree(). Add length validation to prevent potential buffer overflow.

The advisory is shared at git.kernel.org. The identification of this vulnerability is CVE-2026-43125 since 05/01/2026. The exploitation is known to be easy. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 07/23/2026).

The vulnerability scanner Nessus provides a plugin with the ID 320531 (RHEL 8 : kernel (RHSA-2026:25121)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.12.75, 6.18.16 or 6.19.6 eliminates this vulnerability. Applying the patch 67288113c5e6cf9e659b4065c0ed6f16100e0c71/082083c9fbd99422a0370fe2102144a231c9f5d6/5f053a2e7209d326cbbc07738fa6d6893d307438/080e5563f878c64e697b89e7439d730d0daad882 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 (320531) and CERT Bund (WID-SEC-2026-1405). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

• Google Container-Optimized OS
• Debian Linux
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• SUSE openSUSE
• RESF Rocky Linux
• Microsoft Azure Linux
• Open Source Linux Kernel
• Proxmox Virtual Environment

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
• 6.12.63
• 6.12.64
• 6.12.65
• 6.12.66
• 6.12.67
• 6.12.68
• 6.12.69
• 6.12.70
• 6.12.71
• 6.12.72
• 6.12.73
• 6.12.74
• 6.18.0
• 6.18.1
• 6.18.2
• 6.18.3
• 6.18.4
• 6.18.5
• 6.18.6
• 6.18.7
• 6.18.8
• 6.18.9
• 6.18.10
• 6.18.11
• 6.18.12
• 6.18.13
• 6.18.14
• 6.18.15
• 6.19.0
• 6.19.1
• 6.19.2
• 6.19.3
• 6.19.4
• 6.19.5

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

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Countermeasuresinfo

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Sourcesinfo

Entryinfo

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

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