---
id: CVE-2026-93805
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  wifi: cfg80211: validate rx/tx MLME callback frame lengths before access

  cfg80211_rx_mlme_mgmt() and cfg80211_tx_mlme_mgmt() call tracepoints
  before rejecting frames s…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  wifi: cfg80211: validate rx/tx MLME callback frame lengths before access

  cfg80211_rx_mlme_mgmt() and cfg80211_tx_mlme_mgmt() call tracepoints
  before rejecting frames s…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    0ec738a0d361d7eb37188117166d201f9df622d3
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    8f4127a93cf60d561ad39849a9ac763ba0e14db5
  - >-
    Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <
    d5e4586546974179feca305a94e07fac3e9727fe
  - Linux < 6.12.111
  - Linux < 6.18.53
  - Linux (all versions)
published: '2026-09-24'
updated: '2026-09-25'
sourceUpdated: '2026-09-25T13:17:21.353'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-93805'
references:
  - url: 'https://git.kernel.org/stable/c/0ec738a0d361d7eb37188117166d201f9df622d3'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/8f4127a93cf60d561ad39849a9ac763ba0e14db5'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/d5e4586546974179feca305a94e07fac3e9727fe'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
  - cve.org
ingestedAt: '2026-09-24T16:47:15.897Z'
---

## Overview

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

wifi: cfg80211: validate rx/tx MLME callback frame lengths before access

cfg80211_rx_mlme_mgmt() and cfg80211_tx_mlme_mgmt() call tracepoints
before rejecting frames shorter than the frame-control field. After
that, they only require len >= 2 before dispatching into subtype
handlers that assume their fixed fields are present.

The frames that trip this are not shorter than 2 bytes; they are short
relative to their subtype. mwifiex is a concrete in-tree example on the
length side: mwifiex_process_mgmt_packet() only requires a 4-address
ieee80211_hdr plus the 2-byte firmware length prefix before handing the
frame to cfg80211_rx_mlme_mgmt(). After stripping the length prefix and
removing addr4, pkt_len can be exactly 24: a bare 3-address management
header with no reason-code body. The existing WARN_ON(len < 2) does not
fire on such a frame, and cfg80211_process_deauth() then reads
u.deauth.reason_code as a two-byte access starting at offset 24,
immediately past the 24-byte buffer.

Add a frame-control length gate, then validate each subtype's minimum
frame size in an if/else-if chain that mirrors the dispatch logic. Trace
only after the frame is known to be well-formed.

Side effects of this change:
 - The WARN_ON(len < 2) is dropped. It only guarded the frame_control
   read, never the subtype fixed fields, and it does not fire on the
   frames that actually trigger the out-of-bounds read (which are >= 2).
   The len >= 2 check is kept as the guard before dereferencing
   frame_control, but without the warning: these are exported callbacks
   and a malformed frame from a driver should be dropped silently rather
   than backtraced.
 - cfg80211_tx_mlme_mgmt() previously routed every non-deauth subtype
   through disassociation handling; it now silently ignores unrecognised
   subtypes.

## Remediation

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