CVE-2025-71089

A security vulnerability was found in the Linux kernel's IOMMU Shared Virtual Addressing (SVA) implementation on x86 architecture. When SVA is enabled, the IOMMU caches kernel page table entries. Since the kernel lacks a mechanism to notify the IOMMU when kernel page table pages are freed and reallocated, the IOMMU can retain stale entries pointing to reused memory. This can lead to use-after-free or write-after-free conditions, potentially enabling arbitrary physical memory DMA access or privilege escalation.

This is a significant security vulnerability affecting x86 systems with IOMMU SVA support enabled. While SVA contexts are unprivileged and cannot directly access kernel mappings, the IOMMU still walks and caches intermediate kernel page table entries. An attacker could potentially exploit the stale cache entries to gain arbitrary DMA access or escalate privileges. The fix disables SVA on x86 until proper cache invalidation mechanisms are implemented.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.