CVE-2026-53326: Linux Kernel

Medium severity, CVSS 5.5. EPSS: 0.1% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: debugobjects: Don't call fill_pool() in early boot hardirq context When booting a debug PREEMPT_RT kernel on an ARM64 system, a "inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-W} usage" lockdep warning message was reported to the console. During early boot, interrupts are enabled before the scheduler is enabled. In this window (before SYSTEM_SCHEDULING is set) interrupts can fire and in the hard interrupt context handler attempt to fill the pool This can lead to a deadlock when the interrupt occurred when the interrupt hits a region which holds a lock that is required to be taken in the allocation path. Add a new can_fill_pool() helper and reorder the exception rule and forbid this scenario by excluding allocations from hard interrupt context.

Affected products

• Linux Linux Kernel: from 6.19, before 7.0.13 (fixed in 7.0.13); version 7.1 only

Published 2026-07-01. Last modified 2026-07-23.