CVE-2026-64180 mm/memory_hotplug: fix memory block reference leak on remove
A reference leak in the Linux kernel memory hotplug subsystem can lead to resource exhaustion and denial of service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-64180?
CVE-2026-64180 is a medium-severity memory corruption vulnerability in Linux kernel, published on 19 Jul 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
mm/memory_hotplug: fix memory block reference leak on remove
Patch series "mm: Fix memory block leaks and locking", v2.
This series fixes two memory block device reference leaks and one locking issue around the per-memory_block hwpoison counter.
This patch (of 2):
remove_memory_blocks_and_altmaps() looks up each memory block with find_memory_block(), which acquires a reference to the memory block device.
That reference is never dropped on this path, resulting in a leaked device reference when removing memory blocks and their altmaps. Drop the reference after retrieving mem->altmap and clearing mem->altmap, before removing the memory block device.
Which versions are affected by CVE-2026-64180?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-64180?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-64180 being exploited?
There is no known exploitation of CVE-2026-64180 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2026-64180, DEBIAN-CVE-2026-64180, GHSA-8rwj-765p-2628, UBUNTU-CVE-2026-64180.