xen — security advisory
PCI devices with RMRRs not deassigned correctly Certain PCI devices in a system might be assigned Reserved Memory Regions (specified via Reserved Memory Region Reporting, "RMRR"). These are typically used for platform tasks such as legacy USB emulation. If such a device is passed through to a guest, then on guest shutdown the device is not properly deassigned. The IOMMU configuration for these devices which are not properly deassigned ends up pointing to a freed data structure, including the IO Pagetables. Subsequent DMA or interrupts from the device will have unpredictable behaviour, ranging from IOMMU faults to memory corruption.
- Products
- xen
- Affected versions
- Not specified
- Fixed versions
- 4.14.3+32-g9de3671772-1
- CVEs
- CVE-2021-28702
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 00:21 UTC · Revision 1
Source evidence
PCI devices with RMRRs not deassigned correctly Certain PCI devices in a system might be assigned Reserved Memory Regions (specified via Reserved Memory Region Reporting, "RMRR"). These are typically used for platform tasks such as legacy USB emulation. If such a device is passed through to a guest, then on guest shutdown the device is not properly deassigned. The IOMMU configuration for these devices which are not properly deassigned ends up pointing to a freed data structure, including the IO Pagetables. Subsequent DMA or interrupts from the device will have unpredictable behaviour, ranging from IOMMU faults to memory corruption.
osv:DEBIAN-CVE-2021-28702
xen
Fixed versions: 4.14.3+32-g9de3671772-1
xen
Fixed versions: 4.14.3+32-g9de3671772-1
xen
Fixed versions: 4.14.3+32-g9de3671772-1
Complete source record
{
"id": "656b6e555bbbe4e8f8e240c6e63596f9226e9c59e2b749dfa22c18bad0484684",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2021-28702",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2021-28702",
"summary": "PCI devices with RMRRs not deassigned correctly Certain PCI devices in a system might be assigned Reserved Memory Regions (specified via Reserved Memory Region Reporting, \"RMRR\"). These are typically used for platform tasks such as legacy USB emulation. If such a device is passed through to a guest, then on guest shutdown the device is not properly deassigned. The IOMMU configuration for these devices which are not properly deassigned ends up pointing to a freed data structure, including the IO Pagetables. Subsequent DMA or interrupts from the device will have unpredictable behaviour, ranging from IOMMU faults to memory corruption.",
"evidence": "osv:DEBIAN-CVE-2021-28702",
"products": [
{
"name": {
"value": "xen",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "4.14.3+32-g9de3671772-1",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "xen",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "4.14.3+32-g9de3671772-1",
"evidence": "/affected/1/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "xen",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "4.14.3+32-g9de3671772-1",
"evidence": "/affected/2/ranges"
}
],
"affected_versions": []
}
],
"severity": "high",
"structured": {
"id": "DEBIAN-CVE-2021-28702",
"aliases": [
"DEBIAN-CVE-2021-28702"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "4.14.3+32-g9de3671772-1"
}
]
}
],
"package": {
"name": "xen",
"purl": "pkg:deb/debian/xen?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2021-28702.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "4.14.3+32-g9de3671772-1"
}
]
}
],
"package": {
"name": "xen",
"purl": "pkg:deb/debian/xen?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2021-28702.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "4.14.3+32-g9de3671772-1"
}
]
}
],
"package": {
"name": "xen",
"purl": "pkg:deb/debian/xen?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2021-28702.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-23T18:03:12.449869256Z",
"provider": "osv",
"upstream": [
"CVE-2021-28702"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2021-28702"
]
},
"related_cves": [
{
"value": "CVE-2021-28702",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 420806,
"published_at": "2021-10-06T14:15:07.23+00:00"
}