---
id: "CVE-2026-98699"
kind: "vulnerability"
aliases: ["CVE-2026-98699"]
title: "Linux kernel: mesh Wi-Fi fast transmit path can use freed memory"
severity: "unknown"
cvss: null
epss: null
exploited: false
status: "open"
category: "infrastructure"
products: []
ecosystems: []
tags: ["infrastructure", "linux-kernel", "mesh-networking", "wifi"]
not_affected_if: ["no-mesh-configured"]
published_at: "2026-10-18T16:17:23+00:00"
first_seen_at: "2026-10-23T21:57:16+00:00"
updated_at: "2026-10-25T05:18:56+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-98699", "first_seen_at": "2026-10-23T21:57:16+00:00"}]
---

# Linux kernel: mesh Wi-Fi fast transmit path can use freed memory

In the Linux kernel's mac80211 wireless stack, a mesh path can be freed while a fast transmit cache entry still points to it, because a lookup can re-insert the entry after deletion has flushed the cache. The sources do not state what an attacker gains beyond a use-after-free, so the impact is unconfirmed.

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

## How to check

- unknown

## Fix

- Update the Linux kernel to a release that includes the mac80211 mesh fast xmit deletion fix (the sources do not name a version).

## Timeline

- 2026-10-23T21:57:16+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-98699

## From the sources

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

wifi: mac80211: fix mesh fast xmit path deletion UAF

mesh_fast_tx_cache() stores raw mesh_path pointers. Path deletion
flushes the cache and then frees the path with kfree_rcu(), but a
lookup that already holds the path can insert a new cache entry
after the flush. The cache then points at freed memory.

Set MESH_PATH_DELETED before flushing, and skip inserting a cache
entry if the path or MPP path is already deleted. Check this under
the cache walk lock so it is ordered with the flush. Use WRITE_ONCE()
for the deletion flag updates because the cache check reads flags
without taking state_lock.

---

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