Overview
CVE-2025-41729 is a high-severity vulnerability affecting devices utilizing the Modbus protocol. This vulnerability allows an unauthenticated remote attacker to trigger a denial-of-service (DoS) condition by sending a specially crafted Modbus read command. Successful exploitation can disrupt critical operations in industrial control systems (ICS) and SCADA environments.
Technical Details
The vulnerability stems from insufficient input validation when processing Modbus read commands. An attacker can craft a malicious request that, when parsed by the vulnerable device, consumes excessive resources, leading to a denial of service. Specifically, the crafted read command could request an unusually large data range, overwhelming the device’s processing capabilities and causing it to become unresponsive.
No authentication is required to exploit this vulnerability, making it easily exploitable remotely, assuming network access to the vulnerable device.
CVSS Analysis
- CVSS Score: 7.5 (HIGH)
- CVSS Vector: (Hypothetical, as it requires calculation based on complete factors) Likely something like: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Explanation: A score of 7.5 indicates a high-severity vulnerability. The ‘AV:N’ (Network) component signifies that the vulnerability can be exploited over a network. ‘AC:L’ (Low Attack Complexity) means the attack is relatively easy to execute. ‘PR:N’ (No Privileges Required) indicates that the attacker does not need any special privileges to exploit the vulnerability. ‘UI:N’ (No User Interaction) means that no user interaction is required. ‘A:H’ (High Availability Impact) confirms the significant impact on availability due to the denial-of-service condition.
Possible Impact
The exploitation of CVE-2025-41729 can have severe consequences, including:
- Disruption of Industrial Processes: The DoS condition can interrupt critical industrial processes, leading to production downtime and financial losses.
- Safety Concerns: In certain industries, a disruption of control systems can have safety implications, potentially leading to hazardous situations.
- Loss of Visibility: The affected device becoming unresponsive can result in a loss of visibility into the industrial process, hindering monitoring and control efforts.
Mitigation and Patch Steps
To mitigate the risk posed by CVE-2025-41729, the following steps are recommended:
- Apply the Vendor Patch: The primary mitigation is to apply the official patch released by the device vendor. Contact your vendor immediately for availability and instructions.
- Network Segmentation: Implement network segmentation to isolate critical industrial control systems from the wider network and untrusted sources. This limits the potential attack surface.
- Access Control Lists (ACLs): Implement ACLs on network devices to restrict access to the Modbus ports (typically port 502) only to authorized IP addresses.
- Intrusion Detection Systems (IDS): Deploy and configure intrusion detection systems to monitor network traffic for malicious Modbus commands and alert administrators to suspicious activity.
- Rate Limiting: If possible, configure rate limiting on the Modbus interface to limit the number of requests processed per unit of time, reducing the impact of a DoS attack.
- Regular Security Audits: Conduct regular security audits of your industrial control systems to identify and address potential vulnerabilities.
References
VDE Security Advisory: VDE-2025-094
NIST Cybersecurity Framework
CISA Industrial Control Systems
