---
id: CVE-2026-74336
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  wifi: mac80211: bound S1G TIM PVB walk to the TIM element

  ieee80211_s1g_check_tim() parses the S1G Partial Virtual Bitmap (PVB) of a
  received TIM element
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  wifi: mac80211: bound S1G TIM PVB walk to the TIM element

  ieee80211_s1g_check_tim() parses the S1G Partial Virtual Bitmap (PVB) of a
  received TIM element. The TIM is h…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= e0c47c6229c25b54440fe1f84a0ff533942290b1 <
    68cf46755894d495b432e21f9e25637030d8b075
  - >-
    Linux >= e0c47c6229c25b54440fe1f84a0ff533942290b1 <
    3abc13ec3ac28c343ad7e7b7496e807b924f0edd
  - >-
    Linux >= e0c47c6229c25b54440fe1f84a0ff533942290b1 <
    b224d18b1e5d1cddfc67f63f41d80023b2ec8889
  - Linux 6.18
published: '2026-08-15'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T11:17:45.190'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-74336'
references:
  - url: 'https://git.kernel.org/stable/c/3abc13ec3ac28c343ad7e7b7496e807b924f0edd'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/68cf46755894d495b432e21f9e25637030d8b075'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/b224d18b1e5d1cddfc67f63f41d80023b2ec8889'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
  - cve.org
epss: 0.00198
epssPercentile: 0.08884
ingestedAt: '2026-10-15T11:00:41.679Z'
---

## Overview

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

wifi: mac80211: bound S1G TIM PVB walk to the TIM element

ieee80211_s1g_check_tim() parses the S1G Partial Virtual Bitmap (PVB) of a
received TIM element. The TIM is handed in as the element payload:
ieee802_11_parse_elems_full() stores elems->tim = elem->data and
elems->tim_len = elem->datalen (net/mac80211/parse.c), so the valid bytes
are [tim, tim + tim_len).

When walking the encoded blocks the function passes the walker an end
sentinel of (const u8 *)tim + tim_len + 2, i.e. two bytes past the end of
the element. ieee80211_s1g_find_target_block() loops while (ptr + 1 <= end)
and dereferences ptr (and the per-mode ieee80211_s1g_len_*() helpers read
*ptr), so it can read up to two bytes beyond the TIM element -- an
out-of-bounds read of adjacent skb/heap data when the TIM is the last
element in the frame. The +2 appears to account for the element id/len
header, but tim already points past that header at the element payload, so
the addend is wrong.

Pass the correct element end, (const u8 *)tim + tim_len.

## Remediation

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