CVE-2026-97421 RDMA/umem: Be careful about boundary conditions in ib_umem_find_best_pgsz()
Integer overflow in Linux kernel RDMA memory handling can cause boundary condition errors, potentially leading to system instability or crashes.
- 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-2026-97421?
CVE-2026-97421 is a high-severity vulnerability in Linux, published on 24 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:
RDMA/umem: Be careful about boundary conditions in ib_umem_find_best_pgsz()
Several corner cases, especially important on 32 bits:
- umem->iova is u64, the function argument should pass in u64 or iova will be truncated - Check that the length is not too large for the iova - Check that lengths > 4G don't overflow the GENMASK
Which versions are affected by CVE-2026-97421?
How do I fix CVE-2026-97421?
Apply the vendor's patch.
Is CVE-2026-97421 being exploited?
There is no known exploitation of CVE-2026-97421 in the wild and no public exploit code.
Sources
Also known as AZL-103682, BELL-CVE-2026-97421, DEBIAN-CVE-2026-97421, GHSA-rfxq-r256-5mj8, UBUNTU-CVE-2026-97421.