vulnerability
Debian: CVE-2021-28702: xen -- security update
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 5 | (AV:L/AC:L/Au:N/C:P/I:P/A:P) | Oct 6, 2021 | Nov 4, 2022 | Aug 15, 2025 |
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.
Solution
Explore Exposure Command
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