CVE Catalog

CVE-2026-64183

MediumCVSS 5.5
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.12%

2th percentile - higher than 2% of all known CVEs

Summary

In the Linux kernel, a vulnerability was found where the EFI runtime workqueue was allocated too late, causing a NULL pointer dereference when ACPI PRM calls were made early during boot. The fix moves the workqueue allocation to an earlier initcall (postcore).

Risk Assessment

The risk involves potential system hangs or kernel panics during boot when ACPI invokes PRM handlers before the EFI workqueue is ready, which could prevent the system from starting correctly on hardware using PRM.

Recommendation

Update the Linux kernel to a version containing the fix commit. Monitor your distribution for the appropriate security patch.

Other vulnerabilities in Linux kernel

See all
Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: efi: Allocate runtime workqueue before ACPI init Since commit 5894cf571e14 ("acpi/prmt: Use EFI runtime sandbox to invoke PRM handlers") ACPI PRM calls are delegated to a workqueue which runs in a kernel thread, making it easier to detect and mitigate faulting memory accesses performed by the firmware. Rafael reports that such PRM accesses may occur before efisubsys_init() executes, which is where the workqueue is allocated, leading to NULL pointer dereferences. Since acpi_init() [which triggers the early PRM accesses] executes as a subsys_initcall() as well, and has its own dependencies that may be sensitive to initcall ordering, deferring acpi_init() is not an option. So instead, split off the workqueue allocation into its own postcore initcall, as this is the only missing piece to allow EFI runtime calls to be made. This ensures that EFI runtime call (including PRM calls) are accessible to all code running at subsys_initcall() level.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS