CVE-2023-46839 - CVE House
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Status published Unknown CVE-2023-46839

pci: phantom functions assigned to incorrect contexts

Vulnerability 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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:

  • This issue was discovered by Roger Pau Monné of XenServer.

References

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Affected Vendor

Affected Software

Xen
Vulnerable Versions:
consult Xen advisory XSA-449

Timeline

Official Publish: March 20th, 2024
Last Modified: November 4th, 2025
Added to House: July 22nd, 2026

CVSS Vectors

No vector data available

Weaknesses (CWE)

No CWE data available

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.