ubuntu-cve-2026-23554
Vulnerability from osv_ubuntu
Published
2026-03-23 07:16
Modified
2026-05-20 15:26
Summary
Details
The Intel EPT paging code uses an optimization to defer flushing of any cached EPT state until the p2m lock is dropped, so that multiple modifications done under the same locked region only issue a single flush. Freeing of paging structures however is not deferred until the flushing is done, and can result in freed pages transiently being present in cached state. Such stale entries can point to memory ranges not owned by the guest, thus allowing access to unintended memory regions.
Severity
7.8 (High)
N/A (UNKNOWN)
References
{
"affected": [
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libxen-4.6",
"binary_version": "4.6.5-0ubuntu1.4"
},
{
"binary_name": "libxenstore3.0",
"binary_version": "4.6.5-0ubuntu1.4"
},
{
"binary_name": "xen-hypervisor-4.4-amd64",
"binary_version": "4.6.5-0ubuntu1.4"
},
{
"binary_name": "xen-hypervisor-4.4-arm64",
"binary_version": "4.6.5-0ubuntu1.4"
},
{
"binary_name": "xen-hypervisor-4.4-armhf",
"binary_version": "4.6.5-0ubuntu1.4"
},
{
"binary_name": "xen-hypervisor-4.5-amd64",
"binary_version": "4.6.5-0ubuntu1.4"
},
{
"binary_name": "xen-hypervisor-4.5-arm64",
"binary_version": "4.6.5-0ubuntu1.4"
},
{
"binary_name": "xen-hypervisor-4.5-armhf",
"binary_version": "4.6.5-0ubuntu1.4"
},
{
"binary_name": "xen-hypervisor-4.6-amd64",
"binary_version": "4.6.5-0ubuntu1.4"
},
{
"binary_name": "xen-hypervisor-4.6-arm64",
"binary_version": "4.6.5-0ubuntu1.4"
},
{
"binary_name": "xen-hypervisor-4.6-armhf",
"binary_version": "4.6.5-0ubuntu1.4"
},
{
"binary_name": "xen-system-amd64",
"binary_version": "4.6.5-0ubuntu1.4"
},
{
"binary_name": "xen-system-arm64",
"binary_version": "4.6.5-0ubuntu1.4"
},
{
"binary_name": "xen-system-armhf",
"binary_version": "4.6.5-0ubuntu1.4"
},
{
"binary_name": "xen-utils-4.6",
"binary_version": "4.6.5-0ubuntu1.4"
},
{
"binary_name": "xen-utils-common",
"binary_version": "4.6.5-0ubuntu1.4"
},
{
"binary_name": "xenstore-utils",
"binary_version": "4.6.5-0ubuntu1.4"
}
]
},
"package": {
"ecosystem": "Ubuntu:16.04:LTS",
"name": "xen",
"purl": "pkg:deb/ubuntu/xen@4.6.5-0ubuntu1.4?arch=source\u0026distro=xenial"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"4.5.1-0ubuntu1",
"4.5.1-0ubuntu2",
"4.6.0-1ubuntu1",
"4.6.0-1ubuntu2",
"4.6.0-1ubuntu4",
"4.6.0-1ubuntu4.1",
"4.6.0-1ubuntu4.2",
"4.6.0-1ubuntu4.3",
"4.6.5-0ubuntu1",
"4.6.5-0ubuntu1.1",
"4.6.5-0ubuntu1.2",
"4.6.5-0ubuntu1.4"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libxen-4.9",
"binary_version": "4.9.2-0ubuntu1"
},
{
"binary_name": "libxenstore3.0",
"binary_version": "4.9.2-0ubuntu1"
},
{
"binary_name": "xen-hypervisor-4.6-amd64",
"binary_version": "4.9.2-0ubuntu1"
},
{
"binary_name": "xen-hypervisor-4.6-arm64",
"binary_version": "4.9.2-0ubuntu1"
},
{
"binary_name": "xen-hypervisor-4.6-armhf",
"binary_version": "4.9.2-0ubuntu1"
},
{
"binary_name": "xen-hypervisor-4.7-amd64",
"binary_version": "4.9.2-0ubuntu1"
},
{
"binary_name": "xen-hypervisor-4.7-arm64",
"binary_version": "4.9.2-0ubuntu1"
},
{
"binary_name": "xen-hypervisor-4.7-armhf",
"binary_version": "4.9.2-0ubuntu1"
},
{
"binary_name": "xen-hypervisor-4.8-amd64",
"binary_version": "4.9.2-0ubuntu1"
},
{
"binary_name": "xen-hypervisor-4.8-arm64",
"binary_version": "4.9.2-0ubuntu1"
},
{
"binary_name": "xen-hypervisor-4.8-armhf",
"binary_version": "4.9.2-0ubuntu1"
},
{
"binary_name": "xen-hypervisor-4.9-amd64",
"binary_version": "4.9.2-0ubuntu1"
},
{
"binary_name": "xen-hypervisor-4.9-arm64",
"binary_version": "4.9.2-0ubuntu1"
},
{
"binary_name": "xen-hypervisor-4.9-armhf",
"binary_version": "4.9.2-0ubuntu1"
},
{
"binary_name": "xen-system-amd64",
"binary_version": "4.9.2-0ubuntu1"
},
{
"binary_name": "xen-system-arm64",
"binary_version": "4.9.2-0ubuntu1"
},
{
"binary_name": "xen-system-armhf",
"binary_version": "4.9.2-0ubuntu1"
},
{
"binary_name": "xen-utils-4.9",
"binary_version": "4.9.2-0ubuntu1"
},
{
"binary_name": "xen-utils-common",
"binary_version": "4.9.2-0ubuntu1"
},
{
"binary_name": "xenstore-utils",
"binary_version": "4.9.2-0ubuntu1"
}
]
},
"package": {
"ecosystem": "Ubuntu:18.04:LTS",
"name": "xen",
"purl": "pkg:deb/ubuntu/xen@4.9.2-0ubuntu1?arch=source\u0026distro=bionic"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"4.9.0-0ubuntu3",
"4.9.0-0ubuntu4",
"4.9.2-0ubuntu1"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libxencall1",
"binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu2.3"
},
{
"binary_name": "libxendevicemodel1",
"binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu2.3"
},
{
"binary_name": "libxenevtchn1",
"binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu2.3"
},
{
"binary_name": "libxenforeignmemory1",
"binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu2.3"
},
{
"binary_name": "libxengnttab1",
"binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu2.3"
},
{
"binary_name": "libxenmisc4.11",
"binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu2.3"
},
{
"binary_name": "libxenstore3.0",
"binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu2.3"
},
{
"binary_name": "libxentoolcore1",
"binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu2.3"
},
{
"binary_name": "libxentoollog1",
"binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu2.3"
},
{
"binary_name": "xen-hypervisor-4.11-amd64",
"binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu2.3"
},
{
"binary_name": "xen-hypervisor-4.11-arm64",
"binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu2.3"
},
{
"binary_name": "xen-hypervisor-4.11-armhf",
"binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu2.3"
},
{
"binary_name": "xen-hypervisor-4.9-amd64",
"binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu2.3"
},
{
"binary_name": "xen-hypervisor-4.9-arm64",
"binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu2.3"
},
{
"binary_name": "xen-hypervisor-4.9-armhf",
"binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu2.3"
},
{
"binary_name": "xen-hypervisor-common",
"binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu2.3"
},
{
"binary_name": "xen-system-amd64",
"binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu2.3"
},
{
"binary_name": "xen-system-arm64",
"binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu2.3"
},
{
"binary_name": "xen-system-armhf",
"binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu2.3"
},
{
"binary_name": "xen-utils-4.11",
"binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu2.3"
},
{
"binary_name": "xen-utils-common",
"binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu2.3"
},
{
"binary_name": "xenstore-utils",
"binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu2.3"
}
]
},
"package": {
"ecosystem": "Ubuntu:20.04:LTS",
"name": "xen",
"purl": "pkg:deb/ubuntu/xen@4.11.3+24-g14b62ab3e5-1ubuntu2.3?arch=source\u0026distro=focal"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"4.9.2-0ubuntu2",
"4.9.2-0ubuntu6",
"4.9.2-0ubuntu7",
"4.11.3+24-g14b62ab3e5-1ubuntu1",
"4.11.3+24-g14b62ab3e5-1ubuntu2",
"4.11.3+24-g14b62ab3e5-1ubuntu2.2",
"4.11.3+24-g14b62ab3e5-1ubuntu2.3"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libxencall1",
"binary_version": "4.16.0-1~ubuntu2.1"
},
{
"binary_name": "libxendevicemodel1",
"binary_version": "4.16.0-1~ubuntu2.1"
},
{
"binary_name": "libxenevtchn1",
"binary_version": "4.16.0-1~ubuntu2.1"
},
{
"binary_name": "libxenforeignmemory1",
"binary_version": "4.16.0-1~ubuntu2.1"
},
{
"binary_name": "libxengnttab1",
"binary_version": "4.16.0-1~ubuntu2.1"
},
{
"binary_name": "libxenhypfs1",
"binary_version": "4.16.0-1~ubuntu2.1"
},
{
"binary_name": "libxenmisc4.16",
"binary_version": "4.16.0-1~ubuntu2.1"
},
{
"binary_name": "libxenstore4",
"binary_version": "4.16.0-1~ubuntu2.1"
},
{
"binary_name": "libxentoolcore1",
"binary_version": "4.16.0-1~ubuntu2.1"
},
{
"binary_name": "libxentoollog1",
"binary_version": "4.16.0-1~ubuntu2.1"
},
{
"binary_name": "xen-hypervisor-4.16-amd64",
"binary_version": "4.16.0-1~ubuntu2.1"
},
{
"binary_name": "xen-hypervisor-4.16-arm64",
"binary_version": "4.16.0-1~ubuntu2.1"
},
{
"binary_name": "xen-hypervisor-4.16-armhf",
"binary_version": "4.16.0-1~ubuntu2.1"
},
{
"binary_name": "xen-hypervisor-common",
"binary_version": "4.16.0-1~ubuntu2.1"
},
{
"binary_name": "xen-system-amd64",
"binary_version": "4.16.0-1~ubuntu2.1"
},
{
"binary_name": "xen-system-arm64",
"binary_version": "4.16.0-1~ubuntu2.1"
},
{
"binary_name": "xen-system-armhf",
"binary_version": "4.16.0-1~ubuntu2.1"
},
{
"binary_name": "xen-utils-4.16",
"binary_version": "4.16.0-1~ubuntu2.1"
},
{
"binary_name": "xen-utils-common",
"binary_version": "4.16.0-1~ubuntu2.1"
},
{
"binary_name": "xenstore-utils",
"binary_version": "4.16.0-1~ubuntu2.1"
}
]
},
"package": {
"ecosystem": "Ubuntu:22.04:LTS",
"name": "xen",
"purl": "pkg:deb/ubuntu/xen@4.16.0-1~ubuntu2.1?arch=source\u0026distro=jammy"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"4.11.4+24-gddaaccbbab-1ubuntu2",
"4.16.0-1~ubuntu2",
"4.16.0-1~ubuntu2.1"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libxencall1t64",
"binary_version": "4.17.3+10-g091466ba55-1.1ubuntu3"
},
{
"binary_name": "libxendevicemodel1t64",
"binary_version": "4.17.3+10-g091466ba55-1.1ubuntu3"
},
{
"binary_name": "libxenevtchn1t64",
"binary_version": "4.17.3+10-g091466ba55-1.1ubuntu3"
},
{
"binary_name": "libxenforeignmemory1t64",
"binary_version": "4.17.3+10-g091466ba55-1.1ubuntu3"
},
{
"binary_name": "libxengnttab1t64",
"binary_version": "4.17.3+10-g091466ba55-1.1ubuntu3"
},
{
"binary_name": "libxenhypfs1t64",
"binary_version": "4.17.3+10-g091466ba55-1.1ubuntu3"
},
{
"binary_name": "libxenmisc4.17t64",
"binary_version": "4.17.3+10-g091466ba55-1.1ubuntu3"
},
{
"binary_name": "libxenstore4t64",
"binary_version": "4.17.3+10-g091466ba55-1.1ubuntu3"
},
{
"binary_name": "libxentoolcore1t64",
"binary_version": "4.17.3+10-g091466ba55-1.1ubuntu3"
},
{
"binary_name": "libxentoollog1t64",
"binary_version": "4.17.3+10-g091466ba55-1.1ubuntu3"
},
{
"binary_name": "xen-hypervisor-4.17-amd64",
"binary_version": "4.17.3+10-g091466ba55-1.1ubuntu3"
},
{
"binary_name": "xen-hypervisor-4.17-arm64",
"binary_version": "4.17.3+10-g091466ba55-1.1ubuntu3"
},
{
"binary_name": "xen-hypervisor-4.17-armhf",
"binary_version": "4.17.3+10-g091466ba55-1.1ubuntu3"
},
{
"binary_name": "xen-hypervisor-common",
"binary_version": "4.17.3+10-g091466ba55-1.1ubuntu3"
},
{
"binary_name": "xen-system-amd64",
"binary_version": "4.17.3+10-g091466ba55-1.1ubuntu3"
},
{
"binary_name": "xen-system-arm64",
"binary_version": "4.17.3+10-g091466ba55-1.1ubuntu3"
},
{
"binary_name": "xen-system-armhf",
"binary_version": "4.17.3+10-g091466ba55-1.1ubuntu3"
},
{
"binary_name": "xen-utils-4.17",
"binary_version": "4.17.3+10-g091466ba55-1.1ubuntu3"
},
{
"binary_name": "xen-utils-common",
"binary_version": "4.17.3+10-g091466ba55-1.1ubuntu3"
},
{
"binary_name": "xenstore-utils",
"binary_version": "4.17.3+10-g091466ba55-1.1ubuntu3"
}
]
},
"package": {
"ecosystem": "Ubuntu:24.04:LTS",
"name": "xen",
"purl": "pkg:deb/ubuntu/xen@4.17.3+10-g091466ba55-1.1ubuntu3?arch=source\u0026distro=noble"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"4.17.2-1",
"4.17.2+55-g0b56bed864-1",
"4.17.2+76-ge1f9cb16e2-1",
"4.17.2+76-ge1f9cb16e2-1ubuntu1",
"4.17.3+10-g091466ba55-1",
"4.17.3+10-g091466ba55-1.1ubuntu2",
"4.17.3+10-g091466ba55-1.1ubuntu3"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libxencall1",
"binary_version": "4.20.0+68-g35cb38b222-1"
},
{
"binary_name": "libxendevicemodel1",
"binary_version": "4.20.0+68-g35cb38b222-1"
},
{
"binary_name": "libxenevtchn1",
"binary_version": "4.20.0+68-g35cb38b222-1"
},
{
"binary_name": "libxenforeignmemory1",
"binary_version": "4.20.0+68-g35cb38b222-1"
},
{
"binary_name": "libxengnttab1",
"binary_version": "4.20.0+68-g35cb38b222-1"
},
{
"binary_name": "libxenhypfs1",
"binary_version": "4.20.0+68-g35cb38b222-1"
},
{
"binary_name": "libxenmisc4.20",
"binary_version": "4.20.0+68-g35cb38b222-1"
},
{
"binary_name": "libxenstore4",
"binary_version": "4.20.0+68-g35cb38b222-1"
},
{
"binary_name": "libxentoolcore1",
"binary_version": "4.20.0+68-g35cb38b222-1"
},
{
"binary_name": "libxentoollog1",
"binary_version": "4.20.0+68-g35cb38b222-1"
},
{
"binary_name": "xen-hypervisor-4.20-amd64",
"binary_version": "4.20.0+68-g35cb38b222-1"
},
{
"binary_name": "xen-hypervisor-4.20-arm64",
"binary_version": "4.20.0+68-g35cb38b222-1"
},
{
"binary_name": "xen-hypervisor-common",
"binary_version": "4.20.0+68-g35cb38b222-1"
},
{
"binary_name": "xen-system-amd64",
"binary_version": "4.20.0+68-g35cb38b222-1"
},
{
"binary_name": "xen-system-arm64",
"binary_version": "4.20.0+68-g35cb38b222-1"
},
{
"binary_name": "xen-utils-4.20",
"binary_version": "4.20.0+68-g35cb38b222-1"
},
{
"binary_name": "xen-utils-common",
"binary_version": "4.20.0+68-g35cb38b222-1"
},
{
"binary_name": "xenstore-utils",
"binary_version": "4.20.0+68-g35cb38b222-1"
}
]
},
"package": {
"ecosystem": "Ubuntu:25.10",
"name": "xen",
"purl": "pkg:deb/ubuntu/xen@4.20.0+68-g35cb38b222-1?arch=source\u0026distro=questing"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"4.20.0-1ubuntu1",
"4.20.0+68-g35cb38b222-1"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libxencall1",
"binary_version": "4.20.2+7-g1badcf5035-2build2"
},
{
"binary_name": "libxendevicemodel1",
"binary_version": "4.20.2+7-g1badcf5035-2build2"
},
{
"binary_name": "libxenevtchn1",
"binary_version": "4.20.2+7-g1badcf5035-2build2"
},
{
"binary_name": "libxenforeignmemory1",
"binary_version": "4.20.2+7-g1badcf5035-2build2"
},
{
"binary_name": "libxengnttab1",
"binary_version": "4.20.2+7-g1badcf5035-2build2"
},
{
"binary_name": "libxenhypfs1",
"binary_version": "4.20.2+7-g1badcf5035-2build2"
},
{
"binary_name": "libxenmisc4.20",
"binary_version": "4.20.2+7-g1badcf5035-2build2"
},
{
"binary_name": "libxenstore4",
"binary_version": "4.20.2+7-g1badcf5035-2build2"
},
{
"binary_name": "libxentoolcore1",
"binary_version": "4.20.2+7-g1badcf5035-2build2"
},
{
"binary_name": "libxentoollog1",
"binary_version": "4.20.2+7-g1badcf5035-2build2"
},
{
"binary_name": "xen-hypervisor-4.20-amd64",
"binary_version": "4.20.2+7-g1badcf5035-2build2"
},
{
"binary_name": "xen-hypervisor-4.20-arm64",
"binary_version": "4.20.2+7-g1badcf5035-2build2"
},
{
"binary_name": "xen-hypervisor-common",
"binary_version": "4.20.2+7-g1badcf5035-2build2"
},
{
"binary_name": "xen-system-amd64",
"binary_version": "4.20.2+7-g1badcf5035-2build2"
},
{
"binary_name": "xen-system-arm64",
"binary_version": "4.20.2+7-g1badcf5035-2build2"
},
{
"binary_name": "xen-utils-4.20",
"binary_version": "4.20.2+7-g1badcf5035-2build2"
},
{
"binary_name": "xen-utils-common",
"binary_version": "4.20.2+7-g1badcf5035-2build2"
},
{
"binary_name": "xenstore-utils",
"binary_version": "4.20.2+7-g1badcf5035-2build2"
}
]
},
"package": {
"ecosystem": "Ubuntu:26.04:LTS",
"name": "xen",
"purl": "pkg:deb/ubuntu/xen@4.20.2+7-g1badcf5035-2build2?arch=source\u0026distro=resolute"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"4.20.0+68-g35cb38b222-1",
"4.20.2+7-g1badcf5035-2",
"4.20.2+7-g1badcf5035-2build2"
]
}
],
"aliases": [],
"details": "The Intel EPT paging code uses an optimization to defer flushing of any cached EPT state until the p2m lock is dropped, so that multiple modifications done under the same locked region only issue a single flush. Freeing of paging structures however is not deferred until the flushing is done, and can result in freed pages transiently being present in cached state. Such stale entries can point to memory ranges not owned by the guest, thus allowing access to unintended memory regions.",
"id": "UBUNTU-CVE-2026-23554",
"modified": "2026-05-20T15:26:04Z",
"published": "2026-03-23T07:16:00Z",
"references": [
{
"type": "REPORT",
"url": "https://ubuntu.com/security/CVE-2026-23554"
},
{
"type": "REPORT",
"url": "https://www.cve.org/CVERecord?id=CVE-2026-23554"
},
{
"type": "REPORT",
"url": "https://xenbits.xen.org/xsa/advisory-480.html"
}
],
"related": [],
"schema_version": "1.7.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H",
"type": "CVSS_V3"
},
{
"score": "medium",
"type": "Ubuntu"
}
],
"upstream": [
"CVE-2026-23554"
]
}
Loading…
Loading…
Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Loading…
Loading…