---
id: CVE-2026-98340
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  wifi: cfg80211: only group hidden BSSes with beacon entries

  When a probe response for an unknown BSS comes in, __cfg80211_bss_update()
  looks for an existing entry with…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  wifi: cfg80211: only group hidden BSSes with beacon entries

  When a probe response for an unknown BSS comes in, __cfg80211_bss_update()
  looks for an existing entry with…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 4593c4cbe1c96b3995727dc42f6aa103f4ff5afc <
    4cd6a518ce7527284bbc9baab5fa2453a7d477c2
  - >-
    Linux >= 4593c4cbe1c96b3995727dc42f6aa103f4ff5afc <
    74ed0d992f392c75e1969415527e06df3f7a4034
  - >-
    Linux >= 4593c4cbe1c96b3995727dc42f6aa103f4ff5afc <
    3658093df69849daf4f813a8f087f358e13be203
  - >-
    Linux >= 4593c4cbe1c96b3995727dc42f6aa103f4ff5afc <
    73365b81630b57e1a1f9d50dc87281797855c2ac
  - >-
    Linux >= 4593c4cbe1c96b3995727dc42f6aa103f4ff5afc <
    7405dd19bda4537a2843637d8d7bed1efd4776cf
  - >-
    Linux >= 4593c4cbe1c96b3995727dc42f6aa103f4ff5afc <
    86235be788094131912e9bd8412b358d91d99f49
  - >-
    Linux >= 4593c4cbe1c96b3995727dc42f6aa103f4ff5afc <
    332ea1502c46f53375cb109fa82bfaff818f3a41
  - >-
    Linux >= 4593c4cbe1c96b3995727dc42f6aa103f4ff5afc <
    068843ed0902c552a13860c5ec6b2ca65b57a065
  - Linux 3.9
published: '2026-10-06'
updated: '2026-10-06'
sourceUpdated: '2026-10-06T09:18:26.720'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-98340'
references:
  - url: 'https://git.kernel.org/stable/c/068843ed0902c552a13860c5ec6b2ca65b57a065'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/332ea1502c46f53375cb109fa82bfaff818f3a41'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/3658093df69849daf4f813a8f087f358e13be203'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/4cd6a518ce7527284bbc9baab5fa2453a7d477c2'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/73365b81630b57e1a1f9d50dc87281797855c2ac'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/7405dd19bda4537a2843637d8d7bed1efd4776cf'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/74ed0d992f392c75e1969415527e06df3f7a4034'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/86235be788094131912e9bd8412b358d91d99f49'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
  - cve.org
ingestedAt: '2026-10-06T08:50:17.399Z'
---

## Overview

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

wifi: cfg80211: only group hidden BSSes with beacon entries

When a probe response for an unknown BSS comes in, __cfg80211_bss_update()
looks for an existing entry with the same BSSID and a hidden (zero-length
or NUL-filled) SSID, and if it finds one it groups them, using the beacon
IEs from the existing entry.

But that could find another entry without a beacon, if it was also from a
probe response (with SSID), so there's a group without beacon elements.

If a beacon with a hidden SSID for that BSSID arrives later,
cfg80211_combine_bsses() goes looking for the probe response entries that
belong to it - i.e. entries with the same BSSID and channel that have no
beacon IEs - and finds those two. They are already grouped with each
other, so it hits its

  WARN_ON_ONCE(bss->pub.hidden_beacon_bss)
  WARN_ON_ONCE(!list_empty(&bss->hidden_list))

which are there because an entry without beacon elements is not supposed
to be part of a group yet.

Only combine entries when a beacon was already received, ones that are
kept separate will be combined when a beacon arrives.

## Remediation

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