CVE-2026-97548 xfs: fix the rtrmap and rtrefcount _maxlevels_ondisk functions
A flaw in the Linux kernel XFS filesystem allows out-of-bounds memory access, potentially leading to system crashes or arbitrary code execution.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-97548?
CVE-2026-97548 is a high-severity memory corruption vulnerability in Linux, published on 25 Sep 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official description
In the Linux kernel, the following vulnerability has been resolved:
xfs: fix the rtrmap and rtrefcount _maxlevels_ondisk functions
The _maxlevels_ondisk functions are used to compute the size of in-memory btree cursors for each btree type. Unfortunately, LOLLM noticed that the rtrmap and rtrefcount versions of these functions forget to account for the inode root, which means that we could access beyond the end of the cursor given a sufficiently large btree. Fix this.
Which versions are affected by CVE-2026-97548?
How do I fix CVE-2026-97548?
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-2026-97548 being exploited?
There is no known exploitation of CVE-2026-97548 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-97548, DEBIAN-CVE-2026-97548, GHSA-w932-ggqv-vxgq, UBUNTU-CVE-2026-97548.