CVE-2024-22044 in SENTRON 3KC ATC6 Expansion Module Ethernet
Summary
by MITRE • 03/12/2024
A vulnerability has been identified in SENTRON 3KC ATC6 Expansion Module Ethernet (3KC9000-8TL75) (All versions). Affected devices expose an unused, unstable http service at port 80/tcp on the Modbus-TCP Ethernet. This could allow an attacker on the same Modbus network to create a denial of service condition that forces the device to reboot.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 03/12/2024
The vulnerability CVE-2024-22044 affects the SENTRON 3KC ATC6 Expansion Module Ethernet device model 3KC9000-8TL75 across all versions. This represents a significant security concern for industrial control systems that rely on Modbus-TCP communication protocols for device management and monitoring. The affected device operates within industrial environments where network stability and continuous operation are critical for maintaining operational integrity. The presence of an unused and unstable HTTP service on port 80/tcp within the Modbus-TCP Ethernet interface creates an unexpected attack surface that adversaries can exploit to disrupt normal operations. This vulnerability specifically targets the network infrastructure of industrial automation systems where Modbus protocol is commonly deployed for communication between programmable logic controllers and various field devices.
The technical flaw manifests as an unintended HTTP service that remains active and accessible on port 80/tcp within the device's Modbus-TCP Ethernet interface. This unstable service represents a deviation from standard device behavior where only necessary communication protocols should be active. The HTTP service operates on a port typically reserved for web-based communication, creating confusion in network traffic analysis and potentially exposing the device to attacks that target web application vulnerabilities. The service's instability suggests that it may not properly handle incoming requests or may contain implementation flaws that could be leveraged by malicious actors. The vulnerability's exploitation requires network access to the same Modbus network segment, making it particularly concerning for environments where physical network security is not adequately enforced.
The operational impact of this vulnerability extends beyond simple service disruption to potentially compromising the entire industrial control system's reliability. When exploited, the vulnerability can force the device to reboot, creating a denial of service condition that may interrupt critical automation processes. In industrial environments where continuous operation is essential, such disruptions can lead to production halts, quality control issues, and potential safety hazards. The device reboot condition can occur without proper authentication or authorization, making it particularly dangerous as any network-connected attacker can potentially trigger this condition. This vulnerability directly impacts the availability aspect of the CIA triad and can be categorized under CWE-1004 which addresses insecure default configurations in network services.
Mitigation strategies should focus on network segmentation and access control measures to prevent unauthorized access to the Modbus network segment. Network administrators should disable or remove the unused HTTP service from port 80/tcp through firmware updates or configuration changes when available. Implementing network access control lists can help restrict access to only authorized devices and users within the Modbus network. The vulnerability aligns with ATT&CK technique T1190 which covers exploit public-facing application, and T1499 which addresses network disruption through denial of service. Organizations should also consider implementing network monitoring solutions to detect unusual traffic patterns on port 80/tcp that might indicate exploitation attempts. Regular security assessments of industrial control systems should include verification of unused services and ports to prevent similar vulnerabilities from persisting in operational environments.