CVE-2019-18424 Privilege escalation in n/a
Attackers with PCI pass-through access can corrupt host memory via DMA during device deassignment, leading to host OS privilege escalation.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2019-18424?
CVE-2019-18424 is a medium-severity vulnerability in Debian Debian Linux, published on 31 Oct 2019. It can only be exploited from the same machine or local network, with no action from the victim.
Official 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.
Weakness: CWE-78
Which versions are affected by CVE-2019-18424?
It affects 4 products.
Products include Debian Debian Linux, Fedoraproject Fedora, Opensuse Leap, Xen Xen.
How do I fix CVE-2019-18424?
Apply the vendor's patch.
Is CVE-2019-18424 being exploited?
There is no known exploitation of CVE-2019-18424 in the wild and no public exploit code.
Other vulnerabilities in Debian Debian Linux
Sources
Also known as ALPINE-CVE-2019-18424, DEBIAN-CVE-2019-18424, GHSA-3q68-jh6h-39cm, UBUNTU-CVE-2019-18424.