---
id: CVE-2026-98422
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  wifi: mac80211: reset the AP_VLAN tailroom counter on ifdown

  On ifup, AP_VLAN interfaces get crypto_tx_tailroom_needed_cnt from
  the AP interface, but it's never decrem…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  wifi: mac80211: reset the AP_VLAN tailroom counter on ifdown

  On ifup, AP_VLAN interfaces get crypto_tx_tailroom_needed_cnt from
  the AP interface, but it's never decrem…
severity: medium
published: '2026-10-14'
updated: '2026-10-14'
sourceUpdated: '2026-10-14T14:17:53.737'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-98422'
references:
  - url: 'https://git.kernel.org/stable/c/304a874670a0b6ab5589a7f60b4af0251797b121'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/3d76b45e8432c0d75fcb9e90d92eaa3176898adf'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/4504f3960dc4501c73be9f99eabda2e26e9db41e'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/4b54d01b48445b66c9e576de92b90a3a3ae7b34a'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/7775759e3cb35ef5a571b2d877c2a9b70a5d5f08'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/875835377d8d62c849b4eb03a7abfafa71d7668f'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/b0b32d3f163d24ea7134380666193bf398e9dc0b'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/f6b34a7d64324faf28eedc0f8678b0f832f1cc36'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98422.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-98422'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2552230'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-98422'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-98422'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98422.mbox
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
ingestedAt: '2026-10-14T15:36:13.989Z'
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= f9dca80b98caac8b4bfb43a2edf1e9f877ccf322 <
    b0b32d3f163d24ea7134380666193bf398e9dc0b
  - >-
    Linux >= f9dca80b98caac8b4bfb43a2edf1e9f877ccf322 <
    f6b34a7d64324faf28eedc0f8678b0f832f1cc36
  - >-
    Linux >= f9dca80b98caac8b4bfb43a2edf1e9f877ccf322 <
    304a874670a0b6ab5589a7f60b4af0251797b121
  - >-
    Linux >= f9dca80b98caac8b4bfb43a2edf1e9f877ccf322 <
    7775759e3cb35ef5a571b2d877c2a9b70a5d5f08
  - >-
    Linux >= f9dca80b98caac8b4bfb43a2edf1e9f877ccf322 <
    3d76b45e8432c0d75fcb9e90d92eaa3176898adf
  - >-
    Linux >= f9dca80b98caac8b4bfb43a2edf1e9f877ccf322 <
    4b54d01b48445b66c9e576de92b90a3a3ae7b34a
  - >-
    Linux >= f9dca80b98caac8b4bfb43a2edf1e9f877ccf322 <
    875835377d8d62c849b4eb03a7abfafa71d7668f
  - >-
    Linux >= f9dca80b98caac8b4bfb43a2edf1e9f877ccf322 <
    4504f3960dc4501c73be9f99eabda2e26e9db41e
  - Linux 4.1
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-617
epss: 0.0022
epssPercentile: 0.12449
---

## Overview

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

wifi: mac80211: reset the AP_VLAN tailroom counter on ifdown

On ifup, AP_VLAN interfaces get crypto_tx_tailroom_needed_cnt from
the AP interface, but it's never decremented again unless the AP is
also brought down. Thus, bringing the same AP_VLAN up again will
increment the counter again and eventually hit the sanity check:

  WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt !=
               master->crypto_tx_tailroom_needed_cnt);

Reset it on ifdown to avoid that.

## Remediation

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

## Vendor advisories

- **Red Hat VEX** · Low · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, … · updated 2026-10-18 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98422.json)