CVE-2026-63940

CRITICAL9.3

KVM: SEV: Ignore Port I/O requests of length '0'

Published Jul 19, 2026

Modified 1 months ago

Details

In the Linux kernel, the following vulnerability has been resolved:

KVM: SEV: Ignore Port I/O requests of length '0'

Explicitly ignore Port I/O requests of length '0' (or count '0'), so that setting up the software scratch area (and other code) doesn't have to worry about underflowing the length, and to allow for WARNing on trying to configure the scratch area with len==0.

References

WEB

https://git.kernel.org/stable/c/2254972d4d69e279ba4e87bf0968eb08ad0d3c92

WEB

https://git.kernel.org/stable/c/3988bd2723de407ae90fa7a6f6029b4e60238c58

WEB

https://git.kernel.org/stable/c/3b6035bc6bff20e89752ce4358bc4c9a9d5883f2

WEB

https://git.kernel.org/stable/c/c30cde934c7813b4e3069765dac64ce3d31e34f2

ADVISORY

https://www.cve.org/CVERecord?id=CVE-2026-63940

CVSS Analysis