---
id: CVE-2026-89445
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  iommufd: Fix UAF in selftest IOPF reporting

  IOMMUFD selftest TRIGGER_IOPF borrows an attach handle from
  group->pasid_array without synchronizing against PASID detach,
  …
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  iommufd: Fix UAF in selftest IOPF reporting

  IOMMUFD selftest TRIGGER_IOPF borrows an attach handle from
  group->pasid_array without synchronizing against PASID detach,
  …
severity: high
cvss: 8.8
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H'
cwe:
  - CWE-825
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= ddee19971081b42615d62f4fdada21274708ed4d <
    fd2e7ac94d6d813548b021473c3dddc30c8c07d1
  - >-
    Linux >= ddee19971081b42615d62f4fdada21274708ed4d <
    cab2895729516799384d48560e6fca105fb3f927
  - >-
    Linux >= ddee19971081b42615d62f4fdada21274708ed4d <
    e27e90bde68b2ab92e63ed19caad1ef57188bea0
  - >-
    Linux >= ddee19971081b42615d62f4fdada21274708ed4d <
    8c07df7cdfcf52f1ff276c588612aabc6c6b8399
  - Linux 6.11
published: '2026-09-11'
updated: '2026-10-03'
sourceUpdated: '2026-10-03T11:17:42.070'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-89445'
references:
  - url: 'https://git.kernel.org/stable/c/8c07df7cdfcf52f1ff276c588612aabc6c6b8399'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/cab2895729516799384d48560e6fca105fb3f927'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/e27e90bde68b2ab92e63ed19caad1ef57188bea0'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/fd2e7ac94d6d813548b021473c3dddc30c8c07d1'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89445.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-89445'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2532116'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-89445'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-89445'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89445.mbox
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
epss: 0.00168
epssPercentile: 0.06065
scores:
  nvd: 8.8
  vendor: 7
  cna: 8.8
ingestedAt: '2026-09-14T15:23:07.475Z'
---

## Overview

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

iommufd: Fix UAF in selftest IOPF reporting

IOMMUFD selftest TRIGGER_IOPF borrows an attach handle from
group->pasid_array without synchronizing against PASID detach,
then a concurrent iommu_report_device_fault() can dereference
that borrowed handle's domain pointer after the detach erases
the handle and frees the backing struct iommufd_attach_handle.
TRIGGER_IOPF then dereferences the freed handle, causing a UAF.

Fix by adding a iopf_rwsem in mock_dev to follow the expected design
of a real driver. Hold its read side across the whole
iommu_report_device_fault() call, and its write side around every
path that attaches, detaches, or replaces a device domain.
This can block new reports and drains in-flight reports before an old
attach handle or the IOPF fault parameter can be removed.
Also take the write side while registering a mock device, since
it can invoke the mock driver's default-domain attach callback.

## Remediation

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

## Vendor advisories

- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · updated 2026-09-18 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89445.json)