CPENT Iot And OT Exploitation Practice Question
A penetration tester is evaluating a Zigbee-based smart home lighting network. Using a Texas Instruments CC2531 USB dongle flashed with Sniffer firmware, the tester captures over-the-air packets. To decrypt the Zigbee application layer payload in Wireshark, what critical piece of cryptographic material must the tester input into Wireshark's Zigbee decryption settings?
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
The 128-bit Zigbee Network Key (NWK key)
Zigbee networks encrypt application data using a Network Key. To inspect encrypted application payloads in Wireshark, the Network Key must be provided in the Zigbee protocol preferences.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
The 128-bit Zigbee Network Key (NWK key)
Why this is correct
Wireshark requires the 128-bit Network Key to decrypt standard Zigbee frames captured over the air.
- ✗
The device's physical serial number printed on the casing
Why it's wrong here
Physical serial numbers are static identifiers used during manufacturing or onboarding, not the session/network decryption key.
- ✗
The manufacturer's IEEE 802.15.4 MAC address
Why it's wrong here
MAC addresses are link-layer identifiers and do not provide the cryptographic material needed to decrypt encrypted payload data.
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The Wi-Fi WPA2 pre-shared key of the local router
Why it's wrong here
Zigbee operates on the 2.4 GHz ISM band using IEEE 802.15.4, which is completely independent of Wi-Fi WPA2 encryption keys.
About these practice questions
One of 274 original CPENT practice questions on Courseiva, each with a full explanation and wrong-answer analysis — not exam dumps or protected exam content. Learn why practice questions differ from exam dumps →
JA
Written and reviewed by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
Last reviewed August 2026 · checked against the official EC-Council exam blueprint
This CPENT practice question is part of Courseiva's free EC-Council certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the CPENT exam.