CVE-2026-97617 ring-buffer: Check resize_disabled before publishing the new subbuf order
A race condition in the Linux kernel ring buffer allows local attackers to corrupt memory mappings, potentially leading to privilege escalation or code execution.
- 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-2026-97617?
CVE-2026-97617 is a vulnerability in Linux, published on 25 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:
ring-buffer: Check resize_disabled before publishing the new subbuf order
ring_buffer_subbuf_order_set() stores the new order and only then walks the CPUs, returning -EBUSY if any of them has resizing disabled. A user mapped buffer has resizing disabled, and __rb_map_vma() reads buffer->subbuf_order without buffer->mutex, so an mmap of an already mapped CPU racing the failing order change sizes the mapping with the new order and inserts pages past the sub-buffer into the VMA.
Check the CPUs before storing the new order.
Which versions are affected by CVE-2026-97617?
How do I fix CVE-2026-97617?
Apply the vendor's patch.
Is CVE-2026-97617 being exploited?
There is no known exploitation of CVE-2026-97617 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-97617, DEBIAN-CVE-2026-97617, GHSA-vwfx-985h-jqvx, UBUNTU-CVE-2026-97617.