---
id: "CVE-2026-98704"
kind: "vulnerability"
aliases: ["CVE-2026-98704"]
title: "Linux kernel: Wi-Fi association reads freed memory on non-transmitted MBSSID profiles"
severity: "unknown"
cvss: null
epss: null
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["embedded", "laptops", "linux-kernel", "mac80211", "runtime", "wifi"]
not_affected_if: ["no-wifi", "wired-only"]
published_at: "2026-10-18T16:17:23+00:00"
first_seen_at: "2026-10-23T21:57:16+00:00"
updated_at: "2026-10-25T05:18:52+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-98704", "first_seen_at": "2026-10-23T21:57:16+00:00"}]
---

# Linux kernel: Wi-Fi association reads freed memory on non-transmitted MBSSID profiles

When a Linux machine associates with a non-transmitted MBSSID Wi-Fi profile, the mac80211 code reads memory it has already freed while picking the channel and applying HT settings. The sources do not describe what an attacker can achieve beyond the memory read and crash risk.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Run `uname -r` and compare against the kernel version that contains the upstream fix for CVE-2026-98704 (unknown in the sources)
- Check whether the mac80211 Wi-Fi stack is in use with `lsmod | grep mac80211`

## Fix

- Update the Linux kernel to a release that includes the upstream commit for CVE-2026-98704 (exact version unknown in the sources)

## Timeline

- 2026-10-23T21:57:16+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-98704

## From the sources

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

wifi: mac80211: keep fallback association elements alive

Associating to a non-transmitted MBSSID profile reads freed memory while
determining the operating channel and applying HT capabilities.

When an association response omits WMM, HT, or VHT information,
ieee80211_assoc_config_link() parses the cached BSS IEs and copies the
missing element pointers out of that fallback parse. For a
non-transmitted MBSSID profile those pointers refer to merged-profile
storage owned by the parse object, and the fallback block frees that
object at its end. The copied pointers are used afterwards to determine
the operating channel, configure bandwidth, and apply HT capabilities.

Keep the fallback parse result alive until association setup finishes.

[reorder variable declaration]

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_