Linux Kernel up to 6.12.10 cond_resched denial of service

Summaryinfo

A vulnerability, which was classified as critical, was found in Linux Kernel up to 6.12.10. The impacted element is the function cond_resched. The manipulation results in denial of service. This vulnerability is known as CVE-2025-21694. No exploit is available. You should upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in Linux Kernel up to 6.12.10. Affected is the function cond_resched. The manipulation with an unknown input leads to a denial of service vulnerability. CWE is classifying the issue as CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. This is going to have an impact on availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: fs/proc: fix softlockup in __read_vmcore (part 2) Since commit 5cbcb62dddf5 ("fs/proc: fix softlockup in __read_vmcore") the number of softlockups in __read_vmcore at kdump time have gone down, but they still happen sometimes. In a memory constrained environment like the kdump image, a softlockup is not just a harmless message, but it can interfere with things like RCU freeing memory, causing the crashdump to get stuck. The second loop in __read_vmcore has a lot more opportunities for natural sleep points, like scheduling out while waiting for a data write to happen, but apparently that is not always enough. Add a cond_resched() to the second loop in __read_vmcore to (hopefully) get rid of the softlockups.

The advisory is shared for download at git.kernel.org. This vulnerability is traded as CVE-2025-21694 since 12/29/2024. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 216985 (Debian dla-4076 : linux-config-6.1 - security update), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.4.290, 5.10.234, 5.15.177, 6.1.127, 6.6.74 or 6.12.11 eliminates this vulnerability. Applying the patch 84c4ed15626574c9ac6c1039ba9c137a77bcc7f2/80da29deb88a3a907441fc35bb7bac309f31e713/649b266606bc413407ce315f710c8ce8a88ee30a/65c367bd9d4f43513c7f837df5753bea9561b836/a5a2ee8144c3897d37403a69118c3e3dc5713958/80828540dad0757b6337c6561d49c81038f38d87/cbc5dde0a461240046e8a41c43d7c3b76d5db952 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 (216985), EUVD (EUVD-2025-2643) and CERT Bund (WID-SEC-2025-2855). Once again VulDB remains the best source for vulnerability data.

Affected

• IBM DataPower Gateway
• Dell PowerScale OneFS

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 5.4.289
• 5.10.233
• 5.15.176
• 6.1.126
• 6.6.0
• 6.6.1
• 6.6.2
• 6.6.3
• 6.6.4
• 6.6.5
• 6.6.6
• 6.6.7
• 6.6.8
• 6.6.9
• 6.6.10
• 6.6.11
• 6.6.12
• 6.6.13
• 6.6.14
• 6.6.15
• 6.6.16
• 6.6.17
• 6.6.18
• 6.6.19
• 6.6.20
• 6.6.21
• 6.6.22
• 6.6.23
• 6.6.24
• 6.6.25
• 6.6.26
• 6.6.27
• 6.6.28
• 6.6.29
• 6.6.30
• 6.6.31
• 6.6.32
• 6.6.33
• 6.6.34
• 6.6.35
• 6.6.36
• 6.6.37
• 6.6.38
• 6.6.39
• 6.6.40
• 6.6.41
• 6.6.42
• 6.6.43
• 6.6.44
• 6.6.45
• 6.6.46
• 6.6.47
• 6.6.48
• 6.6.49
• 6.6.50
• 6.6.51
• 6.6.52
• 6.6.53
• 6.6.54
• 6.6.55
• 6.6.56
• 6.6.57
• 6.6.58
• 6.6.59
• 6.6.60
• 6.6.61
• 6.6.62
• 6.6.63
• 6.6.64
• 6.6.65
• 6.6.66
• 6.6.67
• 6.6.68
• 6.6.69
• 6.6.70
• 6.6.71
• 6.6.72
• 6.6.73
• 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

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Once again VulDB remains the best source for vulnerability data.

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