CVE-2026-98475 s390/cmf: Fix virtual vs physical address confusion
A kernel flaw allows firmware to use incorrect addresses for channel measurement data, potentially leading to memory corruption or data exposure on s390 systems.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-98475?
CVE-2026-98475 is a memory corruption vulnerability in Linux, published on 18 Oct 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:
s390/cmf: Fix virtual vs physical address confusion
The measurement block address is an absolute address. Define the associated schib_config and schib fields as dma64_t to enable automatic detection of incorrect assignments. Also add the missing virt_to_dma64() translation.
Without this fix, a wrong address will be used by firmware when storing extended format channel measurement data on kernels built with CONFIG_RANDOMIZE_IDENTITY_BASE=y.
Which versions are affected by CVE-2026-98475?
How do I fix CVE-2026-98475?
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-2026-98475 being exploited?
There is no known exploitation of CVE-2026-98475 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-98475, DEBIAN-CVE-2026-98475, GHSA-p4wm-c7q2-mpq9, UBUNTU-CVE-2026-98475.