---
id: CVE-2025-68760
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  iommu/amd: Fix potential out-of-bounds read in iommu_mmio_show

  In iommu_mmio_write(), it validates the user-provided offset with the
  check: `iommu->dbg_mmio_offset > i…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  iommu/amd: Fix potential out-of-bounds read in iommu_mmio_show

  In iommu_mmio_write(), it validates the user-provided offset with the
  check: `iommu->dbg_mmio_offset > i…
severity: none
published: '2026-01-05'
updated: '2026-10-14'
sourceUpdated: '2026-10-14T19:10:00.297'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2025-68760'
references:
  - url: 'https://git.kernel.org/stable/c/0ec4aaf5f3f559716a6559f3d6d9616e9470bed6'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/a0c7005333f9a968abb058b1d77bbcd7fb7fd1e7'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/b959df804c33913dbfdb90750f2d693502b3d126'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
epss: 0.00184
epssPercentile: 0.07475
ingestedAt: '2026-10-14T19:49:57.552Z'
---

## Overview

In the Linux kernel, the following vulnerability has been resolved:

iommu/amd: Fix potential out-of-bounds read in iommu_mmio_show

In iommu_mmio_write(), it validates the user-provided offset with the
check: `iommu->dbg_mmio_offset > iommu->mmio_phys_end - 4`.
This assumes a 4-byte access. However, the corresponding
show handler, iommu_mmio_show(), uses readq() to perform an 8-byte
(64-bit) read.

If a user provides an offset equal to `mmio_phys_end - 4`, the check
passes, and will lead to a 4-byte out-of-bounds read.

Fix this by adjusting the boundary check to use sizeof(u64), which
corresponds to the size of the readq() operation.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.