CVE-2024-41046

What it actually does

Double-free of socket buffer (skb) objects in the Lantiq ETOP Ethernet driver caused by failure to increment the released descriptor counter, allowing the same skb to be freed repeatedly.

Why it matters to the business

Systems using affected Linux kernels on Lantiq-based Ethernet hardware face risk of kernel crashes, memory corruption, denial of service, or potential escalation to code execution; high ecosystem prevalence in embedded and networking devices increases operational disruption and patching urgency across many deployments.

How an attack unfolds

An attacker with local or network-adjacent access triggers repeated attach/detach operations on the Lantiq ETOP interface (for example via crafted network traffic or device reconfiguration) to cause the driver to release the same skb multiple times, leading to memory corruption that can be leveraged for further exploitation; listed threat actors have shown interest in similar Linux kernel memory issues in zero-day campaigns.

How to fix it

Update the Linux kernel to a version containing commit 1a2db00a554cfda57c397cce79b2804bf9633fec or later; rebuild and deploy the patched kernel on all affected Lantiq-based devices; verify the fix is present by checking the driver source for the descriptor increment correction.

How to confirm the fix worked

Confirm the running kernel includes commit 1a2db00a554cfda57c397cce79b2804bf9633fec; exercise the driver attach/detach paths under load and monitor for double-free warnings or crashes; review dmesg and kernel logs for skb release anomalies before and after the update.

Typical attack path

1. Identify systems running vulnerable Linux kernels with Lantiq ETOP driver enabled
2. Obtain local or adjacent network access to the target interface
3. Trigger repeated skb allocation and detach sequences through network activity or driver manipulation
4. Exploit resulting double-free for memory corruption or control-flow hijacking
5. Establish persistence or move laterally if code execution is achieved

How to detect it

Review kernel logs (dmesg, /var/log/kern.log) for repeated skb free warnings or slab corruption messages around Lantiq ETOP driver activity; look for unusual attach/detach patterns in network interface statistics; correlate with process activity that manipulates the affected Ethernet device.

What your security team should do

• Prioritize patching all systems using the Lantiq ETOP driver within the next maintenance window due to memory corruption severity
• Inventory Linux kernel versions and hardware using Lantiq Ethernet controllers
• Apply the referenced commit or equivalent stable kernel update immediately on exposed devices
• Monitor kernel logs for skb double-free indicators during the transition period
• Consider disabling the driver if the hardware is not required until patches are deployed