CVE-2021-28702

HighCVSS 7.6/10Last modified Jun 17, 2026

Description

PCI devices with RMRRs not deassigned correctly Certain PCI devices in a system might be assigned Reserved Memory Regions (specified via Reserved Memory Region Reporting, "RMRR"). These are typically used for platform tasks such as legacy USB emulation. If such a device is passed through to a guest, then on guest shutdown the device is not properly deassigned. The IOMMU configuration for these devices which are not properly deassigned ends up pointing to a freed data structure, including the IO Pagetables. Subsequent DMA or interrupts from the device will have unpredictable behaviour, ranging from IOMMU faults to memory corruption.

Metrics

CVSS 3.1 7.6/10CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

Weakness enumeration

CWE-269

Affected software

VendorProductVersions
Xenxen>= 4.12.x, < unspecified

References

Timeline

Published
Oct 6, 2021
Last modified
Jun 17, 2026
NVD status
Modified

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CVE-2021-28702: High severity, CVSS 7.6 | Vulnix