cbcvebase.
CVE-2023-46835
published 2024-01-05

CVE-2023-46835: The current setup of the quarantine page tables assumes that the quarantine domain (dom_io) has been initialized with an address width of…

PriorityP426medium5.5CVSS 3.1
AVLACLPRLUINSUCHINAN
EPSS
0.28%
20.3th percentile
The current setup of the quarantine page tables assumes that the quarantine domain (dom_io) has been initialized with an address width of DEFAULT_DOMAIN_ADDRESS_WIDTH (48) and hence 4 page table levels. However dom_io being a PV domain gets the AMD-Vi IOMMU page tables levels based on the maximum (hot pluggable) RAM address, and hence on systems with no RAM above the 512GB mark only 3 page-table levels are configured in the IOMMU. On systems without RAM above the 512GB boundary amd_iommu_quarantine_init() will setup page tables for the scratch page with 4 levels, while the IOMMU will be configured to use 3 levels only, resulting in the last page table directory (PDE) effectively becoming a page table entry (PTE), and hence a device in quarantine mode gaining write access to the page destined to be a PDE. Due to this page table level mismatch, the sink page the device gets read/write access to is no longer cleared between device assignment, possibly leading to data leaks.

Affected

13 ranges
VendorProductVersion rangeFixed in
debianxen< xen 4.17.2+76-ge1f9cb16e2-1~deb12u1 (bookworm)xen 4.17.2+76-ge1f9cb16e2-1~deb12u1 (bookworm)
xenxen>= 0 < 4.15.5-r34.15.5-r3
xenxen>= 0 < 4.16.5-r44.16.5-r4
xenxen>= 0 < 4.16.5-r44.16.5-r4
xenxen>= 0 < 4.17.2-r44.17.2-r4
xenxen>= 0 < 4.17.2-r44.17.2-r4
xenxen>= 0 < 4.17.2-r44.17.2-r4
xenxen>= 0 < 4.17.2-r44.17.2-r4
xenxen>= 0 < 4.17.2-r44.17.2-r4
xenxen>= 0 < 4.17.2-r44.17.2-r4
xenxen>= 0 < 4.17.2+76-ge1f9cb16e2-1~deb12u14.17.2+76-ge1f9cb16e2-1~deb12u1
xenxen>= 0 < 4.17.2+76-ge1f9cb16e2-14.17.2+76-ge1f9cb16e2-1
xenxen>= 0 < 4.17.2+76-ge1f9cb16e2-14.17.2+76-ge1f9cb16e2-1

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
osv5.5MEDIUM
vendor_debian5.5MEDIUM
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