ICS/SCADA Vulnerabilities ICSSCADA Practice Questions (Page 8)

Questions 36–40

1. 36application · medium

   A food processing plant uses a DNP3 protocol for its remote terminal units (RTUs). The protocol is configured with default passwords and no encryption. Which of the following is the most effective mitigation to reduce the risk of unauthorized RTU access?

   • ADisable DNP3 and use a proprietary protocol that is not publicly documented.
   • BIncrease the polling interval to reduce the amount of traffic an attacker can observe.
   • CUse a serial connection instead of Ethernet to make it harder for attackers to access the network.
   • DChange all default passwords to strong, unique credentials and enable DNP3 Secure Authentication if supported.
   Reveal Solution Discussion Select an answer first
2. 37application · medium

   A factory uses a Windows-based HMI that is connected to the internet for remote vendor support. The HMI runs an outdated operating system with known vulnerabilities. The vendor requires this remote access for troubleshooting. Which mitigation is most appropriate to reduce the risk without losing vendor support?

   • ADisconnect the HMI from the internet and require the vendor to visit on-site.
   • BAllow direct internet access but only from the vendor's IP address.
   • CPlace the HMI behind a jump server that requires multi-factor authentication and restrict vendor access to specific times.
   • DUpgrade the HMI operating system to a supported version.
   Reveal Solution Discussion Select an answer first
4. 38application · medium

   A vulnerability assessment of a power utility identifies that the serial communication between a master station and a substation RTU is susceptible to frame injection. An attacker could inject a 'close breaker' command. What is the most significant potential impact of this vulnerability?

   • AUnauthorized closing of a breaker could cause a short circuit, leading to equipment damage and potential safety hazards.
   • BThe attacker could read historical load data from the RTU.
   • CThe RTU would automatically reboot and lose its settings.
   • DThe master station would lose its configuration file.
   Reveal Solution Discussion Select an answer first
5. 39application · medium

   A water utility uses a radio-based SCADA system for remote well pumps. The radio protocol is proprietary and has known vulnerabilities that allow packet injection. The utility cannot replace the radios immediately. Which mitigation is most appropriate?

   • AIncrease the radio transmit power to improve signal strength.
   • BChange the radio frequency to a less common band.
   • CAdd a firewall at the master station that filters radio traffic based on source addresses and allowed commands.
   • DDisable the radio system and use cellular modems instead.
   Reveal Solution Discussion Select an answer first
6. 40application · medium

   A security assessment of a building automation system (BAS) reveals that the BACnet protocol is used without encryption, and the BAS is connected to the corporate network. An attacker could send BACnet commands to change temperature setpoints in a data center. What is the most direct vulnerability in this scenario?

   • AThe BAS controllers have weak passwords.
   • BLack of authentication and encryption in BACnet allows unauthorized control commands.
   • CThe BAS is connected to the corporate network, which is a network segmentation issue.
   • DThe data center cooling system is not redundant.
   Reveal Solution Discussion Select an answer first