CVE-2024-26823

What it actually does

The flaw skips enabling of hardware-specific quirks during ITS probing on ACPI-based systems, causing loss of GICv4 functionality or boot failure on platforms such as HIP07 unless DT boot is used.

Why it matters to the business

ACPI-based ARM servers may experience boot failures or degraded interrupt handling, reducing availability and requiring fallback configurations that limit functionality across a wide range of enterprise hardware.

How an attack unfolds

No remote exploitation path exists; the issue is a kernel probing regression that surfaces automatically on affected firmware during early boot when ACPI tables are processed.

How to fix it

Apply the fix from commit 91a80fff3eeed928b6fba21271f6a9719b22a5d8 or later stable kernels containing this change; rebuild and deploy updated kernel images to all affected systems.

How to confirm the fix worked

Confirm presence of commit 91a80fff3eeed928b6fba21271f6a9719b22a5d8 in the running kernel source or verify GICv4 functionality and successful boot on ACPI platforms post-update.

Typical attack path

1. Boot an affected kernel on ACPI-based GICv3 ITS hardware
2. ITS probe path omits quirk application
3. GICv4 support disabled or system panics

How to detect it

Review early boot logs for ITS probing messages, GICv4 initialization failures, or kernel panics on ACPI platforms; compare running kernel commit history against the fixed revision.

What your security team should do

• Prioritize kernel upgrade on all ACPI-based ARM systems within maintenance windows
• Test boot and GICv4 operation on representative hardware before broad rollout
• Monitor vendor advisories for backported fixes in distribution kernels