---
id: CVE-2026-98031
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  nexthop: Initialize extack in remove_nh_grp_entry()

  remove_nh_grp_entry() prints the extack message when a listener fails
  to replace the reduced nexthop group
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  nexthop: Initialize extack in remove_nh_grp_entry()

  remove_nh_grp_entry() prints the extack message when a listener fails
  to replace the reduced nexthop group. However…
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'
cwe:
  - CWE-824
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 833a1065eeb14437a9a0dfa9dad06ea09894e0b5 <
    35d9ec61466109ef0c2de87067338d929f629527
  - >-
    Linux >= 833a1065eeb14437a9a0dfa9dad06ea09894e0b5 <
    704319510af2179cf03955747d714ab291075c25
  - >-
    Linux >= 833a1065eeb14437a9a0dfa9dad06ea09894e0b5 <
    17acbcd4c5a6ca3dd3f9e52eb203c9175bde609a
  - >-
    Linux >= 833a1065eeb14437a9a0dfa9dad06ea09894e0b5 <
    030c878eaedf0449e2b5401a0a0146d0afcc645e
  - >-
    Linux >= 833a1065eeb14437a9a0dfa9dad06ea09894e0b5 <
    d643cea4248668dc493c513aa7cbc6505eb1a4a9
  - >-
    Linux >= 833a1065eeb14437a9a0dfa9dad06ea09894e0b5 <
    d80677ad7aa5bebfccfd58caa4852b65abe70561
  - >-
    Linux >= 833a1065eeb14437a9a0dfa9dad06ea09894e0b5 <
    5bd9e4e7cdaa03879e9b73b12ab52cceb1edd55b
  - Linux 5.11
published: '2026-09-25'
updated: '2026-10-03'
sourceUpdated: '2026-10-03T11:18:26.073'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-98031'
references:
  - url: 'https://git.kernel.org/stable/c/030c878eaedf0449e2b5401a0a0146d0afcc645e'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/17acbcd4c5a6ca3dd3f9e52eb203c9175bde609a'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/35d9ec61466109ef0c2de87067338d929f629527'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/5bd9e4e7cdaa03879e9b73b12ab52cceb1edd55b'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/704319510af2179cf03955747d714ab291075c25'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/d643cea4248668dc493c513aa7cbc6505eb1a4a9'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/d80677ad7aa5bebfccfd58caa4852b65abe70561'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98031.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-98031'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2541247'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-98031'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-98031'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98031.mbox
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
epss: 0.00173
epssPercentile: 0.06624
cvssSource: vendor
ingestedAt: '2026-09-25T11:06:38.852Z'
---

## Overview

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

nexthop: Initialize extack in remove_nh_grp_entry()

remove_nh_grp_entry() prints the extack message when a listener fails
to replace the reduced nexthop group. However, extack is not
initialized and listeners are not required to set a message when
returning an error. Neither netdevsim nor mlxsw do so when an
allocation fails, resulting in the dereference of an uninitialized
stack pointer.

Fix by zero-initializing extack, as was done in commit 6347c5314cee
("nexthop: initialize extack in nh_res_bucket_migrate()").

## 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 2026-10-17 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98031.json)