CVE-2025-21793: linux kernel — Fix

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.

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CVSS v3.1 Score

5.5

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-369 CWE-369

Affected Products

Vendor	Product	Versions
linux	linux_kernel	6.2 — 6.6.79
linux	linux_kernel	6.7 — 6.12.16
linux	linux_kernel	6.13 — 6.13.4
linux	linux_kernel	All
linux	linux_kernel	All

References

Advisories & Patches

https://git.kernel.org/stable/c/3588b1c0fde2f58d166e3f94a5a58d64b893526c https://git.kernel.org/stable/c/4df6f005bef04a3dd16c028124a1b5684db3922b https://git.kernel.org/stable/c/7434135553bc03809a55803ee6a8dcaae6240d55 https://git.kernel.org/stable/c/966328191b4c389c0f2159fa242915f51cbc1679

Frequently Asked Questions

What is CVE-2025-21793? +

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. It has a CVSS v3.1 base score of 5.5 (MEDIUM).

How severe is CVE-2025-21793? +

CVE-2025-21793 has a CVSS v3.1 score of 5.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2025-21793? +

CVE-2025-21793 affects products from linux, specifically: linux_kernel. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-21793? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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