CVE-2019-18424

Advisory lineage Upstream: 0 Downstream: 14
Modified
Published: 31 Oct 2019, 13:38
Last modified:05 Aug 2024, 01:54

Vulnerability Summary

Overall Risk (default)
medium
28/100
CVSS Score
6.9 MEDIUM
v2.0 (nvd)
EPSS Score
0.12% LOW
0% probability 0.00%
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

31 Oct 2019, 13:38
Published
Vulnerability first disclosed
05 Aug 2024, 01:54
Last Modified
Vulnerability information updated

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.

CVSS Metrics

  • v3.1•MEDIUM•Score: 6.8CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
  • v2.0•MEDIUM•Score: 6.9AV:L/AC:M/Au:N/C:C/I:C/A:C

EPSS Trends

Current EPSS score: 0.12%• Percentile: 30%

Techniques & Countermeasures

  • CWE-78•Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

    The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component.

Affected Systems

  • debian•debian_linux

    9.0 | 10.0

  • fedoraproject•fedora

    29 | 30 | 31

  • opensuse•leap

    15.0

  • xen•xen

    ≤ 4.12.1

References (9)