---
id: CVE-2026-89505
title: 'RDMA/uverbs: Guard legacy bundles without method_elm'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  RDMA/uverbs: Guard legacy bundles without method_elm

  The legacy write() path dispatches through a uverbs_api_write_method, but
  the uverbs_attr_bundle passed to provide…
severity: medium
cvss: 5.5
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'
cvssSource: vendor
cwe:
  - CWE-824
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 7122ff96068a03595bde2fbafaca82ca2ed8084e <
    edae84e5461749ed9adf9fcf5c6e075381040ac3
  - >-
    Linux >= 7122ff96068a03595bde2fbafaca82ca2ed8084e <
    60a42d510113f46de47e86a84bf5758597644487
  - Linux 7.1
published: '2026-09-11'
updated: '2026-10-19'
sourceUpdated: '2026-10-19T08:47:56.727Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-89505'
references:
  - url: 'https://git.kernel.org/stable/c/edae84e5461749ed9adf9fcf5c6e075381040ac3'
  - url: 'https://git.kernel.org/stable/c/60a42d510113f46de47e86a84bf5758597644487'
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89505.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-89505'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2532252'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-89505'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-89505'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89505.mbox
tags:
  - cve.org
  - csaf
  - vex
  - red-hat
epss: 0.00198
epssPercentile: 0.09435
ingestedAt: '2026-09-14T11:11:19.887Z'
---

## Overview

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

RDMA/uverbs: Guard legacy bundles without method_elm

The legacy write() path dispatches through a uverbs_api_write_method, but
the uverbs_attr_bundle passed to provider code does not have an ioctl
method element. If malformed provider input causes the common uverbs
validation code to emit an error message, uverbs_get_handler_fn()
dereferences the uninitialized method_elm pointer.

Initialize method_elm explicitly for legacy bundles and make
uverbs_get_handler_fn() return NULL when no ioctl method is present. The
legacy dispatcher continues to use its local write method, while the ioctl
path continues to use the registered ioctl handler.

## Affected

- `Linux >= 7122ff96068a03595bde2fbafaca82ca2ed8084e < edae84e5461749ed9adf9fcf5c6e075381040ac3`
- `Linux >= 7122ff96068a03595bde2fbafaca82ca2ed8084e < 60a42d510113f46de47e86a84bf5758597644487`
- `Linux 7.1`

## 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 6 · no fix planned: Red Hat Enterprise Linux 6 · updated 2026-09-18 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89505.json)