CVE-2026-93172 mm/mm_init: handle alloc_percpu failure in free_area_init_core_hotplug
A missing allocation check in the Linux kernel memory management subsystem causes a NULL pointer dereference during node hotplug, leading to a system crash.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-93172?
CVE-2026-93172 is a vulnerability in Linux, published on 17 Sep 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/mm_init: handle alloc_percpu failure in free_area_init_core_hotplug
We miss a failed allocation check for pgdat->per_cpu_nodestats, which results in a NULL deref when we offset into the per-cpu area.
Propagate -ENOMEM up the stack and leave per_cpu_nodestats pointing at boot_nodestats so a later online can retry the allocation.
hotadd_init_pgdat() returns NULL on failure, which __try_online_node() already maps to -ENOMEM.
On failure nothing needs to be unwound: - the node is never marked online - per_cpu_nodestats is left pointing at boot_nodestats - __add_memory_resource() cleans up pending memblock resources - later online attempts retry the per_cpu_nodestats allocation
Which versions are affected by CVE-2026-93172?
How do I fix CVE-2026-93172?
Apply the vendor's patch.
Is CVE-2026-93172 being exploited?
There is no known exploitation of CVE-2026-93172 in the wild and no public exploit code.
Sources
Also known as AZL-102893, BELL-CVE-2026-93172, DEBIAN-CVE-2026-93172, GHSA-3775-xr2m-86hx, UBUNTU-CVE-2026-93172.