---
id: "CVE-2026-99196"
kind: "vulnerability"
aliases: ["CVE-2026-99196"]
title: "Linux kernel: au1000 Ethernet driver probe crashes with NULL dereference"
severity: "unknown"
cvss: null
epss: null
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["embedded", "linux-kernel", "mips", "runtime"]
not_affected_if: ["default-config", "no-au1000-hardware"]
published_at: "2026-10-28T11:17:40+00:00"
first_seen_at: "2026-10-28T11:32:37+00:00"
updated_at: "2026-10-28T11:34:07+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-99196", "first_seen_at": "2026-10-28T11:32:37+00:00"}]
---

# Linux kernel: au1000 Ethernet driver probe crashes with NULL dereference

The au1000 Ethernet driver in the Linux kernel assigns its network operations after attaching the PHY, so probing the device dereferences a NULL pointer when CONFIG_NET_SHAPER is enabled. The result is a kernel crash during driver probe, a denial of service rather than a code execution path described in the sources.

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

## How to check

- Check whether the running kernel has CONFIG_NET_SHAPER enabled, for example with `grep CONFIG_NET_SHAPER /boot/config-$(uname -r)`
- Check whether the au1000 Ethernet driver is loaded or built in on the machine, for example with `lsmod | grep au1000`
- unknown for any other exposure check; the sources do not say

## Fix

- Update the Linux kernel to a release that includes the upstream commit moving the netdev_ops assignment before the PHY attach in au1000; the sources do not name the fixed version
- unknown for any other action; the sources do not say

## Timeline

- 2026-10-28T11:32:37+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-99196

## From the sources

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

net: au1000: move setting of netops to fix crash

au1000_probe() calls au1000_mii_probe(), which connects the PHY,
before dev->netdev_ops is assigned. phy_attach_direct() ->
phy_link_topo_add_phy() reads dev->netdev_ops through
netdev_need_ops_lock() since the commit in question, so probing crashes
with a NULL pointer dereference when CONFIG_NET_SHAPER is enabled.

Assign netdev_ops before the PHY attach, as was done for emac in commit
7c9f391ec89c ("net: emac: move setting of netops to fix crash").

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