Vulnerability · Published Mar 20, 2024 · Assigned by XEN
CVE-2023-46839pci: phantom functions assigned to incorrect contexts
Medium 5.3
In plain English
A medium-severity security flaw in Xen from Xen. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.8% (higher than 57% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
PCI devices can make use of a functionality called phantom functions, that when enabled allows the device to generate requests using the IDs of functions that are otherwise unpopulated. This allows a device to extend the number of outstanding requests. Such phantom functions need an IOMMU context setup, but failure to setup the context is not fatal when the device is assigned. Not failing device assignment when such failure happens can lead to the primary device being assigned to a guest, while some of the phantom functions are assigned to a different domain.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.20 | xen | 4.18.0-r3 | ALPINE-CVE-2023-46839 |
| Alpine:v3.21 | xen | 4.18.0-r3 | ALPINE-CVE-2023-46839 |
| Alpine:v3.22 | xen | 4.18.0-r3 | ALPINE-CVE-2023-46839 |
| Alpine:v3.23 | xen | 4.18.0-r3 | ALPINE-CVE-2023-46839 |
| Alpine:v3.24 | xen | 4.18.0-r3 | ALPINE-CVE-2023-46839 |
| Debian:12 | xen | 4.17.3+10-g091466ba55-1~deb12u1 | DEBIAN-CVE-2023-46839 |
| Debian:13 | xen | 4.17.3+10-g091466ba55-1 | DEBIAN-CVE-2023-46839 |
| Debian:14 | xen | 4.17.3+10-g091466ba55-1 | DEBIAN-CVE-2023-46839 |
| Ubuntu:22.04:LTS | xen | no fix listed | UBUNTU-CVE-2023-46839 |
| Ubuntu:24.04:LTS | xen | no fix listed | UBUNTU-CVE-2023-46839 |
| Ubuntu:25.10 | xen | no fix listed | UBUNTU-CVE-2023-46839 |
| Ubuntu:26.04:LTS | xen | no fix listed | UBUNTU-CVE-2023-46839 |
| Ubuntu:26.10 | xen | no fix listed | UBUNTU-CVE-2023-46839 |