CVE-2026-63940

Summary

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.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux291bd20d5d88814a73d43b55b9428feab2f28094 < 3b6035bc6bff20e89752ce4358bc4c9a9d5883f2affected
LinuxLinux291bd20d5d88814a73d43b55b9428feab2f28094 < 2254972d4d69e279ba4e87bf0968eb08ad0d3c92affected
LinuxLinux291bd20d5d88814a73d43b55b9428feab2f28094 < c30cde934c7813b4e3069765dac64ce3d31e34f2affected
LinuxLinux291bd20d5d88814a73d43b55b9428feab2f28094 < 3988bd2723de407ae90fa7a6f6029b4e60238c58affected
LinuxLinux5.11affected
LinuxLinux0 < 5.11unaffected
LinuxLinux6.12.95 <= 6.12.*unaffected
LinuxLinux6.18.35 <= 6.18.*unaffected
LinuxLinux7.0.12 <= 7.0.*unaffected
LinuxLinux7.1 <= *unaffected

Weaknesses

References