In a modern industrial environment, BAS systems have become a core part of facility operations, and their network security is closely related to production safety and data confidentiality. With the deep integration of IT and OT networks, cyber attacks against BAS may cause equipment damage or even production interruption. Therefore, it is extremely important to establish a system network security protection list. This list will help operation and maintenance personnel gradually strengthen system defense from the basic level to the advanced level.
Why BAS systems are easy targets for cyberattacks
BAS systems often use traditional protocols and run for a long time. Network security is often not fully considered in the initial stage of design. Many PLCs and controllers use plain text communication and lack an authentication mechanism. This allows attackers to easily intercept data packets or send malicious instructions. Equipment update cycles in industrial environments are long, and system vulnerabilities are difficult to patch in a timely manner, thus providing opportunities for attackers.
In actual deployment scenarios, the BAS network is often connected to the enterprise's office network, but lacks sufficient security isolation measures. In such a situation, an attacker may use phishing emails to enter the office network, and then move laterally to reach the BAS network. In addition, some operation and maintenance personnel use default passwords or weak passwords for convenience, and do not use secure channels such as virtual private networks when performing remote maintenance. These situations have laid hidden dangers for system security.
How to Assess Cybersecurity Risks of BAS Systems
Start your risk assessment with an asset inventory, documenting all controllers, sensors, actuators, and network devices to clearly identify their system and firmware versions. Then analyze the importance of each component in the system and evaluate the scope of impact that a single point of failure may cause. For key control loops, pay special attention to their communication paths and dependencies.
During the threat modeling phase, it is necessary to identify possible attack vectors, such as unauthorized access to the network, malware infection, and data tampering. It is necessary to combine the value of assets and the possibility of threats to calculate the risk value and determine priorities. For example, a PLC that can directly control key equipment generally has the highest risk level, so protective measures must be taken first.
What basic security protection is needed for BAS network?
The basis of BAS security is network segmentation. The BAS network must be isolated from other networks and divided into different security areas. Industrial firewalls are deployed between different areas to allow only necessary communication traffic to pass through. For critical control networks, you can consider using one-way gateways to achieve physical isolation and completely block external attacks.
Strictly enforce access control, assign minimum-privilege accounts to each user, and block default accounts or change their strong passwords. Remote access via virtual private network with two-factor authentication. Regularly review user permissions and quickly delete accounts of resigned personnel. Close unnecessary service ports on all network devices to reduce the attack surface.
How to choose network security equipment suitable for BAS
The industrial firewall must have a deep packet inspection function. This function must be able to parse industrial protocols such as , etc., and must also perform filtering based on command types. At the same time, the environmental adaptability of the equipment must be taken into consideration to select hardware with a wide temperature range and fanless design to ensure stable operation in industrial sites. When configuring policies, you must follow the principle of least privilege and only allow those necessary protocols and instructions.
Intrusion detection systems need to be deployed at key nodes of the network to monitor abnormal traffic and attack behaviors in real time. It is necessary to choose an IDS that can identify whether there are abnormalities in industrial protocols, such as detecting illegal function codes or abnormal register access conditions. The log audit system needs to centrally collect all device logs and use correlation analysis to discover potential threats. Equipped with global procurement services for weak current intelligent products!
Best Practices for BAS System Vulnerability Management
Implement a vulnerability scanning mechanism to comprehensively inspect the BAS system on a regular basis. Before scanning, the security of the tool must be evaluated to prevent any impact on sensitive equipment. Pay special attention to publicly disclosed industrial equipment vulnerabilities, obtain security patches released by manufacturers in a timely manner, and mitigate systems that cannot be patched immediately with the help of firewall rules and other measures.
A detailed plan needs to be developed to remediate vulnerabilities, prioritizing high-risk vulnerabilities. Before implementing a patch in a production environment, verification must be fully completed in a test environment. For systems that have ceased support, consider upgrading or taking additional protective measures. At the same time, a vulnerability management process should be established with clear responsibilities and timetables to ensure that vulnerabilities can be dealt with in a timely manner.
Daily precautions for BAS security operation and maintenance
During daily operation and maintenance, mobile storage devices must be strictly managed to prevent viruses from spreading through USB flash drives. All host computers should have whitelist software installed to prevent unauthorized programs from running. Configuration and parameter backups need to be carried out regularly to ensure rapid recovery when the system fails. Operators must receive security training to avoid clicking on suspicious links or downloading unknown attachments.
Check the logs recorded by the monitoring system and pay attention to abnormal logins and configuration changes. Carry out security audits according to fixed cycles to verify the effectiveness of policies. Update the network topology diagram to ensure that it matches the actual situation. Develop an emergency response plan, clarify the handling process in the event of an attack, and organize regular drills to improve the team's response capabilities.
What is the most challenging issue you have encountered while working on your BAS security practice? Welcome to share your experience in the comment area. If you find this article useful, please like it and share it with more people in need.
Leave a Reply