KVM: SEV: Ignore Port I/O requests of length '0'
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.
CVE-2026-63940
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-63940
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "291bd20d5d88814a73d43b55b9428feab2f28094",
"lessThan": "bbd3a27e4f99fdcad82d12d79c04a95dff1ff70b",
"versionType": "git"
},
{
"status": "affected",
"version": "291bd20d5d88814a73d43b55b9428feab2f28094",
"lessThan": "3b6035bc6bff20e89752ce4358bc4c9a9d5883f2",
"versionType": "git"
},
{
"status": "affected",
"version": "291bd20d5d88814a73d43b55b9428feab2f28094",
"lessThan": "2254972d4d69e279ba4e87bf0968eb08ad0d3c92",
"versionType": "git"
},
{
"status": "affected",
"version": "291bd20d5d88814a73d43b55b9428feab2f28094",
"lessThan": "c30cde934c7813b4e3069765dac64ce3d31e34f2",
"versionType": "git"
},
{
"status": "affected",
"version": "291bd20d5d88814a73d43b55b9428feab2f28094",
"lessThan": "3988bd2723de407ae90fa7a6f6029b4e60238c58",
"versionType": "git"
}
],
"programFiles": [
"arch/x86/kvm/svm/sev.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "5.11"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "5.11",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.6.160",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.95",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.35",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.0.12",
"versionType": "semver",
"lessThanOrEqual": "7.0.*"
},
{
"status": "unaffected",
"version": "7.1",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"arch/x86/kvm/svm/sev.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-63940
Source reference:
/cveMetadata/cveId
Publisher severity
critical
Source reference: /containers/cna/metrics
- Event
- #46404 · Revision 1
- Added to Heist Feed
- Publisher date