CVE-2026-93251 Linux CVE debrief

Who should care

Linux kernel maintainers, users, and administrators should assess exposure and prioritize verification of affected systems. This includes reviewing Linux kernel configurations and versions, monitoring system logs for potential exploitation attempts, and updating to the latest Linux kernel version if necessary. The vulnerability affects Linux kernel versions prior to the patched one, and users should take steps to verify their systems and apply updates as

Why it matters

A use-after-free vulnerability in the Linux kernel's ACPI bus has been addressed. Linux kernel maintainers and users should assess exposure and prioritize verification of affected systems.

• Verify Linux kernel versions and configurations to determine exposure
• Monitor system logs for potential exploitation attempts
• Prioritize updates to the latest Linux kernel version if necessary

Technical summary

The `acpi_get_first_physical_node()` function in the Linux kernel could return a stale device pointer, leading to a use-after-free issue. A new function, `acpi_bus_get_primary_device()`, has been introduced to mitigate this issue by reference counting the device before returning the pointer. This change helps prevent use-after-free vulnerabilities in the Linux kernel's ACPI bus. The Linux kernel maintainers and users should assess exposure and prioritize verification of affected systems. The technical details of this vulnerability involve the ACPI bus and device management in the Linux kernel

Defensive priority

Linux kernel maintainers and users should assess exposure and prioritize verification of affected systems.

Recommended defensive actions

• Review Linux kernel configurations and versions to determine exposure
• Verify system logs for potential exploitation attempts
• Update to the latest Linux kernel version if necessary
• Monitor system logs for potential exploitation attempts
• Prioritize updates to the latest Linux kernel version if necessary
• Verify Linux kernel versions and configurations to determine exposure
• Review compensating controls for exposed systems while remediation is scheduled and verified

Evidence notes

The CVE record and NVD entry provide details on the vulnerability and its resolution. Linux kernel developers introduced a new function, `acpi_bus_get_primary_device()`, to address the use-after-free issue. This change aims to prevent stale device pointers from being returned by `acpi_get_first_physical_node()`. The Linux kernel maintainers and users should verify affected systems and assess exposure. Evidence from the CVE record and NVD entry suggests that this vulnerability could impact Linux kernel versions prior to the patched one

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.