Linux Kernel up to 6.12.69/6.18.9 smp_mb state issue

Summaryinfo

A vulnerability classified as critical has been found in Linux Kernel up to 6.12.69/6.18.9. Impacted is the function smp_mb. Performing a manipulation results in state issue. This vulnerability is reported as CVE-2026-23213. No exploit exists. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical has been found in Linux Kernel up to 6.12.69/6.18.9. This affects the function smp_mb. The manipulation with an unknown input leads to a state issue vulnerability. CWE is classifying the issue as CWE-371. The impact remains unknown. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: drm/amd/pm: Disable MMIO access during SMU Mode 1 reset During Mode 1 reset, the ASIC undergoes a reset cycle and becomes temporarily inaccessible via PCIe. Any attempt to access MMIO registers during this window (e.g., from interrupt handlers or other driver threads) can result in uncompleted PCIe transactions, leading to NMI panics or system hangs. To prevent this, set the `no_hw_access` flag to true immediately after triggering the reset. This signals other driver components to skip register accesses while the device is offline. A memory barrier `smp_mb()` is added to ensure the flag update is globally visible to all cores before the driver enters the sleep/wait state. (cherry picked from commit 7edb503fe4b6d67f47d8bb0dfafb8e699bb0f8a4)

It is possible to read the advisory at git.kernel.org. This vulnerability is uniquely identified as CVE-2026-23213 since 01/13/2026. 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 03/19/2026).

The vulnerability scanner Nessus provides a plugin with the ID 299426 (Linux Distros Unpatched Vulnerability : CVE-2026-23213), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.12.70 or 6.18.10 eliminates this vulnerability. Applying the patch c1853ebbec980d5c05d431bfd6ded73b1363fd00/cd7ff7fd3e4b77f0b5a292e0926532eaa07c5162/0de604d0357d0d22cbf03af1077d174b641707b6 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 (299426) and CERT Bund (WID-SEC-2026-0462). Be aware that VulDB is the high quality source for vulnerability data.

Affected

• Open Source Linux Kernel

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
• 6.18.0
• 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

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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Sourcesinfo

Entryinfo

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