KVM: x86: Ensure vendor's exit handler runs before fastpath userspace exits
In the Linux kernel, the following vulnerability has been resolved: KVM: x86: Ensure vendor's exit handler runs before fastpath userspace exits Move the handling of fastpath userspace exits into vendor code to ensure KVM runs vendor specific operations that need to run before userspace gains control of the vCPU. E.g. for VMX (and soon to be for SVM as well), KVM needs to flush the PML buffer prior to exiting to userspace, otherwise any memory written by the final KVM_RUN might never be flagged as dirty. Note, waiting to snapshot CR0 and CR3 until svm_handle_exit() is flawed in general, as that risks consuming stale state in a fastpath handler. That will be addressed in a future change.
CVE-2026-64284
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-2026-64284
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": "f7f39c50edb9d336274371953275e0d3503b9b75",
"lessThan": "b3436d9b9b1affe1c3191ac9831308923f5f03c3",
"versionType": "git"
},
{
"status": "affected",
"version": "f7f39c50edb9d336274371953275e0d3503b9b75",
"lessThan": "4ad73ef0e7966ecfe67de0060537b4cb14d9acd4",
"versionType": "git"
},
{
"status": "affected",
"version": "f7f39c50edb9d336274371953275e0d3503b9b75",
"lessThan": "f2ca2b5326211bd38490f0497eb583721ce0bbc0",
"versionType": "git"
},
{
"status": "affected",
"version": "f7f39c50edb9d336274371953275e0d3503b9b75",
"lessThan": "0ffedf43910e44b76c2c1db4e9fbf12b268190c1",
"versionType": "git"
}
],
"programFiles": [
"arch/x86/kvm/svm/svm.c",
"arch/x86/kvm/vmx/vmx.c",
"arch/x86/kvm/x86.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "6.12"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "6.12",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.12.96",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.39",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.1.4",
"versionType": "semver",
"lessThanOrEqual": "7.1.*"
},
{
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"arch/x86/kvm/svm/svm.c",
"arch/x86/kvm/vmx/vmx.c",
"arch/x86/kvm/x86.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-64284
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #40997 · Revision 1
- Added to Heist Feed
- Publisher date