CVE-2023-34326
Assigner: XEN
Published: 2024-01-05T16:30:57.225Z
State: PUBLISHED
title: x86/AMD: missing IOMMU TLB flushing
datePublic: 2023-10-10T11:26:00Z
descriptions: value: The caching invalidation guidelines from the AMD-Vi specification (48882—Rev
3.07-PUB—Oct 2022) is incorrect on some hardware, as devices will malfunction
(see stale DMA mappings) if some fields of the DTE are updated but the IOMMU
TLB is not flushed.

Such stale DMA mappings can point to memory ranges not owned by the guest, thus
allowing access to unindented memory regions.

impacts: descriptions: value: Privilege escalation, Denial of Service (DoS) affecting the entire host,
and information leaks.

affected: defaultStatus: unknown
product: Xen
vendor: Xen
versions: status: unknown
version: consult Xen advisory XSA-442
configurations: value: All Xen versions supporting PCI passthrough are affected.

Only x86 AMD systems with IOMMU hardware are vulnerable.

Only x86 guests which have physical devices passed through to them can
leverage the vulnerability.

workarounds: value: Not passing through physical devices to guests will avoid the vulnerability.

credits: type: finder
value: This issue was discovered by Roger Pau Monné of XenServer.