---
id: CVE-2026-64030
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  wifi: mac80211: bounds-check link_id in ieee80211_ml_epcs

  IEEE80211_MLE_STA_EPCS_CONTROL_LINK_ID is 0x000f, so link_id extracted
  from a PRIO_ACCESS ML element PER_STA_…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  wifi: mac80211: bounds-check link_id in ieee80211_ml_epcs

  IEEE80211_MLE_STA_EPCS_CONTROL_LINK_ID is 0x000f, so link_id extracted
  from a PRIO_ACCESS ML element PER_STA_…
severity: high
cvss: 8.8
cvssVector: 'CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'
cwe:
  - CWE-125
vendor: linux
product: linux_kernel
affected:
  - 'linux_kernel >= 6.15, < 6.18.34'
  - 'linux_kernel >= 6.19, < 7.0.11'
  - linux_kernel = 7.1
patched:
  - linux_kernel 7.0.11
published: '2026-07-19'
updated: '2026-10-13'
sourceUpdated: '2026-10-13T15:29:05.530'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-64030'
references:
  - url: 'https://git.kernel.org/stable/c/2d8379834800c30602f24c71ab7c40f5fe84d200'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/863f1f02a3bd70dbd857b8ac4070292fde8cb4e2'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/f718506edd2d9c6a308ded9d13c632bf7b7d5a2c'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
epss: 0.00375
epssPercentile: 0.29613
ingestedAt: '2026-10-13T15:33:40.027Z'
---

## Overview

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

wifi: mac80211: bounds-check link_id in ieee80211_ml_epcs

IEEE80211_MLE_STA_EPCS_CONTROL_LINK_ID is 0x000f, so link_id extracted
from a PRIO_ACCESS ML element PER_STA_PROFILE subelement can be 0..15.
sdata->link[] has IEEE80211_MLD_MAX_NUM_LINKS (15) entries (indices 0..14),
making index 15 out-of-bounds.

A connected WiFi 7 AP can trigger this by sending an EPCS Enable Response
action frame with a PER_STA_PROFILE subelement where link_id = 15.  The
unsolicited-notification path (dialog_token = 0) is reachable any time
EPCS is already enabled, without any prior client request.

sdata->link[15] reads into the first word of sdata->activate_links_work
(a wiphy_work whose embedded list_head is non-NULL after INIT_LIST_HEAD),
so the NULL check on the result does not catch the invalid access.  The
garbage pointer is then passed to ieee80211_sta_wmm_params(), which
dereferences link->sdata and crashes the kernel.

The same class of bug was fixed for ieee80211_ml_reconfiguration() by
commit 162d331d833d ("wifi: mac80211: bounds-check link_id in
ieee80211_ml_reconfiguration").

## Affected

- `linux_kernel >= 6.15, < 6.18.34`
- `linux_kernel >= 6.19, < 7.0.11`
- `linux_kernel = 7.1`

## Remediation

Upgrade past the affected range:

- `linux_kernel 7.0.11`