Linux Kernel up to 6.6.133/6.12.80/6.18.21/6.19.11 add_adev use after free

Summaryinfo

A vulnerability has been found in Linux Kernel up to 6.6.133/6.12.80/6.18.21/6.19.11 and classified as critical. This issue affects the function add_adev. This manipulation causes use after free. This vulnerability is tracked as CVE-2026-43056. No exploit exists. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.6.133/6.12.80/6.18.21/6.19.11. It has been declared as critical. Affected by this vulnerability is the function add_adev. 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. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: net: mana: fix use-after-free in add_adev() error path If auxiliary_device_add() fails, add_adev() jumps to add_fail and calls auxiliary_device_uninit(adev). The auxiliary device has its release callback set to adev_release(), which frees the containing struct mana_adev. Since adev is embedded in struct mana_adev, the subsequent fall-through to init_fail and access to adev->id may result in a use-after-free. Fix this by saving the allocated auxiliary device id in a local variable before calling auxiliary_device_add(), and use that saved id in the cleanup path after auxiliary_device_uninit().

It is possible to read the advisory at git.kernel.org. This vulnerability is known as CVE-2026-43056 since 05/01/2026. The exploitation appears to be easy. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 06/12/2026).

The vulnerability scanner Nessus provides a plugin with the ID 320627 (RHEL 9 : kernel (RHSA-2026:25217)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.6.134, 6.12.81, 6.18.22 or 6.19.12 eliminates this vulnerability. Applying the patch d88541ffd56d62a61e77209080001eddd4d69815/43f5b19fd190fea20d052bc84741b28031d5baa9/5f4061f8225d18695e5afe9bbf1cb7bd673d7872/e5a75bf026c686b91a7dc6f9c5caf5016745d1fe/c4ea7d8907cf72b259bf70bd8c2e791e1c4ff70f 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 vulnerability database at Tenable (320627). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.6.133
• 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
• 6.12.75
• 6.12.76
• 6.12.77
• 6.12.78
• 6.12.79
• 6.12.80
• 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
• 6.18.16
• 6.18.17
• 6.18.18
• 6.18.19
• 6.18.20
• 6.18.21
• 6.19.0
• 6.19.1
• 6.19.2
• 6.19.3
• 6.19.4
• 6.19.5
• 6.19.6
• 6.19.7
• 6.19.8
• 6.19.9
• 6.19.10
• 6.19.11

License

• open-source

Website

• Vendor: https://www.kernel.org/

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