UBUNTU-CVE-2019-18425

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Source
https://ubuntu.com/security/CVE-2019-18425
Import Source
https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2019/UBUNTU-CVE-2019-18425.json
JSON Data
https://api.osv.dev/v1/vulns/UBUNTU-CVE-2019-18425
Related
Published
2019-10-31T14:15:00Z
Modified
2024-10-15T14:07:03Z
Severity
  • 9.8 (Critical) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H CVSS Calculator
Summary
[none]
Details

An issue was discovered in Xen through 4.12.x allowing 32-bit PV guest OS users to gain guest OS privileges by installing and using descriptors. There is missing descriptor table limit checking in x86 PV emulation. When emulating certain PV guest operations, descriptor table accesses are performed by the emulating code. Such accesses should respect the guest specified limits, unless otherwise guaranteed to fail in such a case. Without this, emulation of 32-bit guest user mode calls through call gates would allow guest user mode to install and then use descriptors of their choice, as long as the guest kernel did not itself install an LDT. (Most OSes don't install any LDT by default). 32-bit PV guest user mode can elevate its privileges to that of the guest kernel. Xen versions from at least 3.2 onwards are affected. Only 32-bit PV guest user mode can leverage this vulnerability. HVM, PVH, as well as 64-bit PV guests cannot leverage this vulnerability. Arm systems are unaffected.

References

Affected packages

Ubuntu:Pro:16.04:LTS / xen

Package

Name
xen
Purl
pkg:deb/ubuntu/xen?arch=src?distro=esm-infra/xenial

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected

Affected versions

4.*

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 

{
    "ubuntu_priority": "medium"
}

Ubuntu:Pro:18.04:LTS / xen

Package

Name
xen
Purl
pkg:deb/ubuntu/xen?arch=src?distro=esm-infra/bionic

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected

Affected versions

4.*

4.9.0-0ubuntu3
4.9.0-0ubuntu4
4.9.2-0ubuntu1

Ecosystem specific 

{
    "ubuntu_priority": "medium"
}

Ubuntu:20.04:LTS / xen

Package

Name
xen
Purl
pkg:deb/ubuntu/xen?arch=src?distro=focal

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
4.11.3+24-g14b62ab3e5-1ubuntu1

Affected versions

4.*

4.9.2-0ubuntu2
4.9.2-0ubuntu6
4.9.2-0ubuntu7

Ecosystem specific 

{
    "availability": "No subscription required",
    "ubuntu_priority": "medium",
    "binaries": [
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "libxen-dev"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "libxencall1"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "libxencall1-dbgsym"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "libxendevicemodel1"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "libxendevicemodel1-dbgsym"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "libxenevtchn1"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "libxenevtchn1-dbgsym"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "libxenforeignmemory1"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "libxenforeignmemory1-dbgsym"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "libxengnttab1"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "libxengnttab1-dbgsym"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "libxenmisc4.11"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "libxenmisc4.11-dbgsym"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "libxenstore3.0"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "libxenstore3.0-dbgsym"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "libxentoolcore1"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "libxentoolcore1-dbgsym"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "libxentoollog1"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "libxentoollog1-dbgsym"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "xen-doc"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "xen-hypervisor-4.11-amd64"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "xen-hypervisor-4.11-arm64"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "xen-hypervisor-4.11-armhf"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "xen-hypervisor-4.9-amd64"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "xen-hypervisor-4.9-arm64"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "xen-hypervisor-4.9-armhf"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "xen-hypervisor-common"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "xen-system-amd64"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "xen-system-arm64"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "xen-system-armhf"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "xen-utils-4.11"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "xen-utils-4.11-dbgsym"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "xen-utils-common"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "xen-utils-common-dbgsym"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "xenstore-utils"
        },
        {
            "binary_version": "4.11.3+24-g14b62ab3e5-1ubuntu1",
            "binary_name": "xenstore-utils-dbgsym"
        }
    ]
}