CVE-2023-54092 KVM: s390: pv: fix index value of replaced ASCE
A flaw in the Linux kernel's KVM s390 module allows a guest to cause a virtual machine crash by triggering invalid page table notifications.
- 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-2023-54092?
CVE-2023-54092 is a high-severity denial of service vulnerability in Linux, published on 24 Dec 2025. 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:
KVM: s390: pv: fix index value of replaced ASCE
The index field of the struct page corresponding to a guest ASCE should be 0. When replacing the ASCE in s390_replace_asce(), the index of the new ASCE should also be set to 0.
Having the wrong index might lead to the wrong addresses being passed around when notifying pte invalidations, and eventually to validity intercepts (VM crash) if the prefix gets unmapped and the notifier gets called with the wrong address.
Which versions are affected by CVE-2023-54092?
How do I fix CVE-2023-54092?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2023-54092 being exploited?
There is no known exploitation of CVE-2023-54092 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2023-54092, DEBIAN-CVE-2023-54092, GHSA-g59x-v7cp-wpr9, UBUNTU-CVE-2023-54092.