CVE-2019-18424

Current Description

An issue was discovered in Xen through 4.12.x allowing attackers to gain host OS privileges via DMA in a situation where an untrusted domain has access to a physical device. This occurs because passed through PCI devices may corrupt host memory after deassignment. When a PCI device is assigned to an untrusted domain, it is possible for that domain to program the device to DMA to an arbitrary address. The IOMMU is used to protect the host from malicious DMA by making sure that the device addresses can only target memory assigned to the guest. However, when the guest domain is torn down, or the device is deassigned, the device is assigned back to dom0, thus allowing any in-flight DMA to potentially target critical host data. An untrusted domain with access to a physical device can DMA into host memory, leading to privilege escalation. Only systems where guests are given direct access to physical devices capable of DMA (PCI pass-through) are vulnerable. Systems which do not use PCI pass-through are not vulnerable.

Referenced by CVEs:CVE-2019-19579

Basic Data

PublishedOctober 31, 2019
Last ModifiedNovember 14, 2019
Assignercve@mitre.org
Data TypeCVE
Data FormatMITRE
Data Version4.0
Problem TypeCWE-78
CVE Data Version4.0

Base Metric V2

CVSS 2 - Version2.0
CVSS 2 - Vector StringAV:L/AC:M/Au:N/C:C/I:C/A:C
CVSS 2 - Access VectorLOCAL
CVSS 2 - Access ComplexityMEDIUM
CVSS 2 - AuthenticationNONE
CVSS 2 - Confidentiality ImpactCOMPLETE
CVSS 2 - Availability ImpactCOMPLETE
CVSS 2 - Base Score6.9
SeverityMEDIUM
Exploitability Score3.4
Impact Score10.0
Obtain All Privilegefalse
Obtain User Privilegefalse
Obtain Other Privilegefalse

Base Metric V3

No data provided.

Configurations

  • OR - Configuration 1
    Cpe VersionPartVendorProductVersionUpdateEditionLanguageSW EditionTarget SWTarget HWOtherVersion Start IncludingVersion End IncludingVersion Start ExcludingVersion End Excluding
    2.3OSXenXen********4.12.1

Vulnerable Software List

VendorProductVersions
Xen Xen *

References

NameSourceURLTags
openSUSE-SU-2019:2506http://lists.opensuse.org/opensuse-security-announce/2019-11/msg00037.htmlSUSE
[oss-security] 20191031 Xen Security Advisory 302 v5 (CVE-2019-18424) - passed through PCI devices may corrupt host memory after deassignmenthttp://www.openwall.com/lists/oss-security/2019/10/31/6MLISTMailing List Mitigation Third Party Advisory
http://xenbits.xen.org/xsa/advisory-302.htmlhttp://xenbits.xen.org/xsa/advisory-302.htmlMISCMitigation Patch Vendor Advisory
FEDORA-2019-865bb16900https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/2BQKXFEDORA
FEDORA-2019-376ec5c107https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/I5WWPFEDORA
FEDORA-2019-cbb732f760https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/IZYATFEDORA
20200114 [SECURITY] [DSA 4602-1] xen security updatehttps://seclists.org/bugtraq/2020/Jan/21BUGTRAQ
GLSA-202003-56https://security.gentoo.org/glsa/202003-56GENTOO
DSA-4602https://www.debian.org/security/2020/dsa-4602DEBIAN