CVE-2023-46839 (GCVE-0-2023-46839)

Vulnerability from cvelistv5 – Published: 2024-03-20 10:35 – Updated: 2025-11-04 18:18
VLAI
Title
pci: phantom functions assigned to incorrect contexts
Summary
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.
Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2024-08-06 14:00 UTC
CWE
Assigner
XEN CNA under the mitre root
CNA scorecard D 56/100 over 48 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Xen Xen Unknown: consult Xen advisory XSA-449
guessed Create a notification for this product.
Date Public
2024-01-30 12:00
Credits
This issue was discovered by Roger Pau Monné of XenServer.
Show details on NVD website
To clipboard 

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