While reviewing a packet capture from an OT network, you notice repeated write-single-coil commands sent over TCP port 502 with no encryption or authentication. To demonstrate the risk to the plant manager, which industrial protocol should you cite as being inherently vulnerable to such manipulation?
TCP port 502 is reserved for Modbus/TCP traffic. The original Modbus specification provides no native encryption or authentication, so commands such as Write Single Coil (function code 0x05) are accepted by compliant devices without verifying the sender's identity or ensuring data integrity. In contrast, OPC UA can use built-in encryption and signing, DNP3 Secure Authentication adds cryptographic controls to DNP3, and ProfiNet IRT implementations that leverage GOOSE over TLS include integrity protections. Therefore, Modbus/TCP is the protocol that remains intrinsically susceptible to clear-text, unauthenticated command injection on port 502.
Ask Bash
Bash is our AI bot, trained to help you pass your exam. AI Generated Content may display inaccurate information, always double-check anything important.
What specific vulnerabilities are associated with Modbus/TCP?
Open an interactive chat with Bash
How does Modbus/TCP compare to OPC UA in terms of security features?
Open an interactive chat with Bash
What is the purpose of the Write Single Coil (function code 0x05) command in Modbus/TCP?
Open an interactive chat with Bash
Why is Modbus/TCP inherently vulnerable?
Open an interactive chat with Bash
What does 'Write Single Coil' mean in Modbus/TCP?
Open an interactive chat with Bash
How does OPC UA provide stronger security compared to Modbus/TCP?
Open an interactive chat with Bash
Certified Ethical Hacker (CEH)
Mobile Platform, IoT, and OT Hacking
Your Score:
Report Issue
Bash, the Crucial Exams Chat Bot
AI Bot
Loading...
Loading...
Loading...
Pass with Confidence.
IT & Cybersecurity Package
You have hit the limits of our free tier, become a Premium Member today for unlimited access.
Military, Healthcare worker, Gov. employee or Teacher? See if you qualify for a Community Discount.
Monthly
$19.99
$19.99/mo
Billed monthly, Cancel any time.
3 Month Pass
$44.99
$14.99/mo
One time purchase of $44.99, Does not auto-renew.
MOST POPULAR
Annual Pass
$119.99
$9.99/mo
One time purchase of $119.99, Does not auto-renew.
BEST DEAL
Lifetime Pass
$189.99
One time purchase, Good for life.
What You Get
All IT & Cybersecurity Package plans include the following perks and exams .