Linux Kernel up to 6.19.5 generic_handle_irq initialization

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.19.5. It has been rated as critical. This affects the function generic_handle_irq. The manipulation leads to initialization. This vulnerability is uniquely identified as CVE-2026-43311. No exploit exists. Upgrading the affected component is advised.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Linux Kernel up to 6.19.5. This issue affects the function generic_handle_irq. The manipulation with an unknown input leads to a initialization vulnerability. Using CWE to declare the problem leads to CWE-665. The product does not initialize or incorrectly initializes a resource, which might leave the resource in an unexpected state when it is accessed or used. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: soc/tegra: pmc: Fix unsafe generic_handle_irq() call Currently, when resuming from system suspend on Tegra platforms, the following warning is observed: WARNING: CPU: 0 PID: 14459 at kernel/irq/irqdesc.c:666 Call trace: handle_irq_desc+0x20/0x58 (P) tegra186_pmc_wake_syscore_resume+0xe4/0x15c syscore_resume+0x3c/0xb8 suspend_devices_and_enter+0x510/0x540 pm_suspend+0x16c/0x1d8 The warning occurs because generic_handle_irq() is being called from a non-interrupt context which is considered as unsafe. Fix this warning by deferring generic_handle_irq() call to an IRQ work which gets executed in hard IRQ context where generic_handle_irq() can be called safely. When PREEMPT_RT kernels are used, regular IRQ work (initialized with init_irq_work) is deferred to run in per-CPU kthreads in preemptible context rather than hard IRQ context. Hence, use the IRQ_WORK_INIT_HARD variant so that with PREEMPT_RT kernels, the IRQ work is processed in hardirq context instead of being deferred to a thread which is required for calling generic_handle_irq(). On non-PREEMPT_RT kernels, both init_irq_work() and IRQ_WORK_INIT_HARD() execute in IRQ context, so this change has no functional impact for standard kernel configurations. [[email protected]: miscellaneous cleanups]

The advisory is shared at git.kernel.org. The identification of this vulnerability is CVE-2026-43311 since 05/01/2026. The exploitation is known to be difficult. 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 06/15/2026).

Upgrading to version 6.19.6 eliminates this vulnerability. Applying the patch 64016227dcdb968b7030eda04304f3d0df5d209d/e6d96073af681780820c94079b978474a8a44413 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 CERT Bund (WID-SEC-2026-1454). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

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

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 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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If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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