KVM: SEV: Do cache maintenance on the source VM *before* clearing SEV state
In the Linux kernel, the following vulnerability has been resolved: KVM: SEV: Do cache maintenance on the source VM *before* clearing SEV state Explicitly flush caches after intra-host migration before clearing "SEV active" on the source VM, as doing cache maintenance afterwards creates a tiny window where memory reclaim could return memory to the host without performing a cache flush, e.g. as pointed out by Sashiko: CPU1 in sev_migrate_from(): src->active = false; CPU2 running concurrent unmap: Since active is false, the automatic cache flush in sev_guest_memory_reclaimed is skipped. The host frees and reallocates the page. CPU1 in sev_migrate_from(): sev_writeback_caches(src_kvm); Executes a hardware cache flush (wbnoinvd), which writes the guest's old dirty ciphertext over the new page owner's data.
CVE-2026-98718
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-2026-98718
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": "37dfb676fafd1eef36fe0bb649607afbb0d5521b",
"lessThan": "8b7d4f68fef96cebe0b6dbb6e5607772337f7369",
"versionType": "git"
},
{
"status": "affected",
"version": "d4cc2dff12116a700add601c0262132cc26e1b2c",
"lessThan": "de83ff6a4d8f3618473bedb3c4400020c22e8a8a",
"versionType": "git"
},
{
"status": "affected",
"version": "93de2a6a4b91b72607136dd656edf03fb399d27f",
"lessThan": "973ea70393e885e540f714904e51bc6cac80e3d7",
"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": "6.18.55",
"lessThan": "6.18.56",
"versionType": "semver"
},
{
"status": "affected",
"version": "7.2.9",
"lessThan": "7.2.10",
"versionType": "semver"
}
],
"programFiles": [
"arch/x86/kvm/svm/sev.c"
],
"defaultStatus": "unaffected"
}
]- Related CVEs
- CVE-2026-98718
Source reference:
/cveMetadata/cveId
Publisher severity
No explicit severity was provided.
- Event
- #38699 · Revision 1
- Added to Heist Feed
- Publisher date