CVE-2025-21793 spi: sn-f-ospi: Fix division by zero
A division by zero error in the Linux kernel's sn-f-ospi SPI driver can cause a system crash, requiring a kernel patch to prevent denial of service.
- 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-2025-21793?
CVE-2025-21793 is a medium-severity denial of service vulnerability in Linux kernel, published on 27 Feb 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:
spi: sn-f-ospi: Fix division by zero
When there is no dummy cycle in the spi-nor commands, both dummy bus cycle bytes and width are zero. Because of the cpu's warning when divided by zero, the warning should be avoided. Return just zero to avoid such calculations.
Weakness: CWE-369
Which versions are affected by CVE-2025-21793?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2025-21793?
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-2025-21793 being exploited?
There is no known exploitation of CVE-2025-21793 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-57761, BELL-CVE-2025-21793, DEBIAN-CVE-2025-21793, GHSA-49w9-5v8p-jcmw, ROOT-OS-UBUNTU-2404-CVE-2025-21793, UBUNTU-CVE-2025-21793.