---
id: CVE-2026-89506
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  RDMA/uverbs: Add UVERBS_ATTR_UHW to UVERBS_METHOD_REG_MR

  The original commit missed that three drivers (mthca, irdma, siw) have UHW
  data associated with reg_mr that ca…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  RDMA/uverbs: Add UVERBS_ATTR_UHW to UVERBS_METHOD_REG_MR

  The original commit missed that three drivers (mthca, irdma, siw) have UHW
  data associated with reg_mr that ca…
severity: medium
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 5b2e45049dc06a876bc6b138218ddeb0814502ef <
    71d5c41ac583df09a7c32199bef7d42de7267d07
  - >-
    Linux >= 5b2e45049dc06a876bc6b138218ddeb0814502ef <
    9e71d0f4944ba5641e01db29b3256c963656d671
  - >-
    Linux >= 5b2e45049dc06a876bc6b138218ddeb0814502ef <
    011199f46f44a9fd93a9e5ab5d7fd1328d80e9bf
  - Linux 6.17
published: '2026-09-11'
updated: '2026-09-11'
sourceUpdated: '2026-09-11T20:19:32.917'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-89506'
references:
  - url: 'https://git.kernel.org/stable/c/011199f46f44a9fd93a9e5ab5d7fd1328d80e9bf'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/71d5c41ac583df09a7c32199bef7d42de7267d07'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/9e71d0f4944ba5641e01db29b3256c963656d671'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89506.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-89506'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2532195'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-89506'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-89506'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89506.mbox
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
ingestedAt: '2026-09-14T13:03:22.755Z'
epss: 0.00206
epssPercentile: 0.09473
cvss: 4.7
cvssVector: 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H'
cvssSource: vendor
cwe:
  - CWE-476
---

## Overview

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

RDMA/uverbs: Add UVERBS_ATTR_UHW to UVERBS_METHOD_REG_MR

The original commit missed that three drivers (mthca, irdma, siw) have UHW
data associated with reg_mr that cannot be passed through the ioctl. They
also assume that the udata cannot be NULL, so failing to pass a valid
udata can trigger a NULL udata crash in those drivers.

This never happens in real systems since in rdma-core ibv_cmd_reg_mr_ex()
does not accept a udata and those three drivers don't use it, however a
malicious userspace could trigger it.

## 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-2026-89506.json)