---
id: CVE-2026-98703
title: 'wifi: mac80211: minstrel_ht: validate fixed rate index'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  wifi: mac80211: minstrel_ht: validate fixed rate index

  The fixed_rate_idx debugfs file is a plain u32 attribute, so any value
  can be written to it.  minstrel_ht_update…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 24f7580e852b5472b51eea322bb78454df0054b8 <
    f8ab6ae1fa360b0191252677f41e781dcb0ffe6e
  - >-
    Linux >= 24f7580e852b5472b51eea322bb78454df0054b8 <
    42aa9feb27b600809414a3c6b0c650bafba542a9
  - >-
    Linux >= 24f7580e852b5472b51eea322bb78454df0054b8 <
    43082d604a9937b94ceb2e484403956d0f363324
  - >-
    Linux >= 24f7580e852b5472b51eea322bb78454df0054b8 <
    15fb9e3cea55fbc378261ce35a32b0f8828f0000
  - Linux 3.1
published: '2026-10-18'
updated: '2026-10-18'
sourceUpdated: '2026-10-18T15:46:33.395Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-98703'
references:
  - url: 'https://git.kernel.org/stable/c/f8ab6ae1fa360b0191252677f41e781dcb0ffe6e'
  - url: 'https://git.kernel.org/stable/c/42aa9feb27b600809414a3c6b0c650bafba542a9'
  - url: 'https://git.kernel.org/stable/c/43082d604a9937b94ceb2e484403956d0f363324'
  - url: 'https://git.kernel.org/stable/c/15fb9e3cea55fbc378261ce35a32b0f8828f0000'
tags:
  - cve.org
ingestedAt: '2026-10-18T16:47:32.515Z'
---

## Overview

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

wifi: mac80211: minstrel_ht: validate fixed rate index

The fixed_rate_idx debugfs file is a plain u32 attribute, so any value
can be written to it.  minstrel_ht_update_stats() then copies the value
into mi->max_tp_rate[] and mi->max_prob_rate, and
minstrel_ht_set_rate() uses MI_RATE_GROUP()/MI_RATE_IDX() to index
minstrel_mcs_groups[] (42 entries) and mi->groups[].rates[] (10 entries)
with it.

Writing e.g. 65535 selects group 4095 and rate index 15, far outside
both arrays.  The out-of-bounds entries are dereferenced and updated as
struct minstrel_rate_stats (retry counts, etc.), so the invalid index
corrupts adjacent kernel memory.  With CONFIG_UBSAN_BOUNDS the access is
reported as an array-index-out-of-bounds in minstrel_ht_set_rate().

Only a valid group/rate pair, or U32_MAX to disable fixed rate
processing, can be used safely, so reject any other value when the
debugfs file is written.

The file is only reachable through a root-only debugfs mount, so this is
not a privilege boundary.  The out-of-bounds access is still a bug that
must not be reachable through a writable debugfs attribute.

## Affected

- `Linux >= 24f7580e852b5472b51eea322bb78454df0054b8 < f8ab6ae1fa360b0191252677f41e781dcb0ffe6e`
- `Linux >= 24f7580e852b5472b51eea322bb78454df0054b8 < 42aa9feb27b600809414a3c6b0c650bafba542a9`
- `Linux >= 24f7580e852b5472b51eea322bb78454df0054b8 < 43082d604a9937b94ceb2e484403956d0f363324`
- `Linux >= 24f7580e852b5472b51eea322bb78454df0054b8 < 15fb9e3cea55fbc378261ce35a32b0f8828f0000`
- `Linux 3.1`

## Remediation

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